diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/AppPresenter.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/AppPresenter.groovy
index e8c606915..be8f6adb8 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/AppPresenter.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/AppPresenter.groovy
@@ -1,7 +1,6 @@
 package life.qbic.portal.offermanager.components
 
 import life.qbic.business.UseCaseFailure
-import life.qbic.portal.offermanager.components.AppViewModel
 
 /**
  *  Handles the presentation of the qoffer-2.0 use cases and its internal data model to the ViewModel.
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/ConfirmationDialog.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/ConfirmationDialog.groovy
index b779e4aaf..d43acd02e 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/ConfirmationDialog.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/ConfirmationDialog.groovy
@@ -1,12 +1,6 @@
 package life.qbic.portal.offermanager.components
 
-import com.vaadin.ui.Alignment
-import com.vaadin.ui.Button
-import com.vaadin.ui.HorizontalLayout
-import com.vaadin.ui.Label
-import com.vaadin.ui.VerticalLayout
-import com.vaadin.ui.Window
-import com.vaadin.ui.themes.ValoTheme
+import com.vaadin.ui.*
 
 /**
  * <h1>Dialog to ask for user confirmation</h1>
@@ -72,4 +66,4 @@ class ConfirmationDialog extends Window{
         })
     }
 
-}
\ No newline at end of file
+}
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/CreateOfferView.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/CreateOfferView.groovy
index 778082d8a..0d456018b 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/CreateOfferView.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/CreateOfferView.groovy
@@ -198,9 +198,13 @@ class CreateOfferView extends FormLayout{
      */
     private static List<ProductItem> getProductItems(List<ProductItemViewModel> items){
         List<ProductItem> productItems = []
-        items.each {
-            productItems.add(new ProductItem(it.quantity,it.product))
+        for (int position = 0; position < items.size(); position++) {
+            ProductItemViewModel currentItem = items.get(position)
+            ProductItem productItem = new ProductItem(currentItem.quantity, currentItem.product)
+            productItem.setOrderPosition(position)
+            productItems.add(productItem)
         }
+
         return productItems
     }
 
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/OfferOverviewView.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/OfferOverviewView.groovy
index db3a366b5..9d25b24ce 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/OfferOverviewView.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/OfferOverviewView.groovy
@@ -3,6 +3,7 @@ package life.qbic.portal.offermanager.components.offer.create
 import com.vaadin.data.provider.ListDataProvider
 import com.vaadin.icons.VaadinIcons
 import com.vaadin.ui.*
+import com.vaadin.ui.components.grid.GridRowDragger
 import com.vaadin.ui.components.grid.HeaderRow
 import com.vaadin.ui.renderers.NumberRenderer
 import com.vaadin.ui.themes.ValoTheme
@@ -42,6 +43,7 @@ class OfferOverviewView extends VerticalLayout {
         ListDataProvider<ProductItemViewModel> dataProvider =
                 new ListDataProvider(createOfferViewModel.getProductItems())
         itemGrid.setDataProvider(dataProvider)
+        enableDraggable(itemGrid)
         setupFilters(dataProvider, itemGrid)
     }
 
@@ -56,6 +58,13 @@ class OfferOverviewView extends VerticalLayout {
                 customerFilterRow)
     }
 
+    static void enableDraggable(Grid<ProductItemViewModel> grid) {
+        new GridRowDragger<>(grid)
+        grid.setStyleGenerator(row -> {
+            return "draggable-row-grab"
+        })
+    }
+
     /**
      * Initializes the start layout for this view
      */
@@ -210,7 +219,6 @@ class OfferOverviewView extends VerticalLayout {
     Small helper object, that will display information
     about individual price positions for offer overviews.
      */
-
     private class PriceField {
 
         String name
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/ProjectInformationView.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/ProjectInformationView.groovy
index 0319f79e0..28555de77 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/ProjectInformationView.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/ProjectInformationView.groovy
@@ -1,6 +1,5 @@
 package life.qbic.portal.offermanager.components.offer.create
 
-
 import com.vaadin.data.ValidationResult
 import com.vaadin.data.Validator
 import com.vaadin.data.ValueContext
@@ -8,7 +7,6 @@ import com.vaadin.icons.VaadinIcons
 import com.vaadin.server.UserError
 import com.vaadin.ui.*
 import com.vaadin.ui.themes.ValoTheme
-import groovy.beans.Bindable
 import life.qbic.portal.offermanager.components.Resettable
 
 /**
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/ProjectManagerSelectionView.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/ProjectManagerSelectionView.groovy
index 9c5e400ec..d615cba30 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/ProjectManagerSelectionView.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/ProjectManagerSelectionView.groovy
@@ -9,7 +9,6 @@ import com.vaadin.ui.themes.ValoTheme
 import life.qbic.datamodel.dtos.business.ProjectManager
 import life.qbic.portal.offermanager.components.GridUtils
 import life.qbic.portal.offermanager.components.Resettable
-import life.qbic.portal.offermanager.components.offer.create.CreateOfferViewModel
 
 /**
  * This class generates a Layout in which the user
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/SelectItemsView.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/SelectItemsView.groovy
index cdac8ba3c..4b8c29e2b 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/SelectItemsView.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/create/SelectItemsView.groovy
@@ -10,6 +10,7 @@ import com.vaadin.server.UserError
 import com.vaadin.shared.data.sort.SortDirection
 import com.vaadin.shared.ui.grid.HeightMode
 import com.vaadin.ui.*
+import com.vaadin.ui.components.grid.GridRowDragger
 import com.vaadin.ui.components.grid.HeaderRow
 import com.vaadin.ui.renderers.NumberRenderer
 import com.vaadin.ui.themes.ValoTheme
@@ -78,6 +79,13 @@ class SelectItemsView extends VerticalLayout implements Resettable {
 
     TabSheet packageAccordion
 
+    static void enableDraggable(Grid<ProductItemViewModel> grid) {
+        new GridRowDragger<>(grid)
+        grid.setStyleGenerator(row -> {
+            return "draggable-row-grab"
+        })
+    }
+
     /**
      * Contains regex for filtering the different product types
      *
@@ -312,6 +320,7 @@ class SelectItemsView extends VerticalLayout implements Resettable {
         generateProductGrid(externalServiceGrid)
         // This grid summarises product items selected for this specific offer, so we set quantity = true
         generateItemGrid(overviewGrid)
+        enableDraggable(overviewGrid)
 
         packageAccordion = new TabSheet()
         packageAccordion.addTab(seqLayout, "Sequencing")
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/overview/projectcreation/CreateProjectView.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/overview/projectcreation/CreateProjectView.groovy
index 58e1654b9..80caf3261 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/overview/projectcreation/CreateProjectView.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/overview/projectcreation/CreateProjectView.groovy
@@ -2,25 +2,13 @@ package life.qbic.portal.offermanager.components.offer.overview.projectcreation
 
 import com.vaadin.icons.VaadinIcons
 import com.vaadin.shared.ui.ContentMode
-import com.vaadin.ui.Alignment
-import com.vaadin.ui.Button
-import com.vaadin.ui.ComboBox
-import com.vaadin.ui.GridLayout
-import com.vaadin.ui.HorizontalLayout
-import com.vaadin.ui.Label
-import com.vaadin.ui.Panel
-import com.vaadin.ui.RadioButtonGroup
-import com.vaadin.ui.TextArea
-import com.vaadin.ui.TextField
-import com.vaadin.ui.VerticalLayout
+import com.vaadin.ui.*
 import com.vaadin.ui.themes.ValoTheme
 import life.qbic.datamodel.dtos.business.Offer
 import life.qbic.datamodel.dtos.projectmanagement.ProjectCode
 import life.qbic.datamodel.dtos.projectmanagement.ProjectIdentifier
 import life.qbic.datamodel.dtos.projectmanagement.ProjectSpace
 
-
-
 /**
  * <h1>Enables a user to create a project based on an existing offer</h1>
  *
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/overview/projectcreation/CreateProjectViewModel.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/overview/projectcreation/CreateProjectViewModel.groovy
index cb3b60efc..179a09d03 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/overview/projectcreation/CreateProjectViewModel.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/overview/projectcreation/CreateProjectViewModel.groovy
@@ -9,8 +9,6 @@ import life.qbic.datamodel.dtos.projectmanagement.ProjectCode
 import life.qbic.datamodel.dtos.projectmanagement.ProjectIdentifier
 import life.qbic.datamodel.dtos.projectmanagement.ProjectSpace
 import life.qbic.portal.offermanager.dataresources.ResourcesService
-import life.qbic.portal.offermanager.dataresources.projects.ProjectResourceService
-import life.qbic.portal.offermanager.dataresources.projects.ProjectSpaceResourceService
 
 /**
  * <h1>Holds the create project state information and logic</h1>
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/update/UpdateOfferView.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/update/UpdateOfferView.groovy
index 4d91214e8..332b72f11 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/update/UpdateOfferView.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/update/UpdateOfferView.groovy
@@ -199,9 +199,13 @@ class UpdateOfferView extends FormLayout {
      */
     private static List<ProductItem> getProductItems(List<ProductItemViewModel> items) {
         List<ProductItem> productItems = []
-        items.each {
-            productItems.add(new ProductItem(it.quantity, it.product))
+        for (int position = 0; position < items.size(); position++) {
+            ProductItemViewModel currentItem = items.get(position)
+            ProductItem productItem = new ProductItem(currentItem.quantity, currentItem.product)
+            productItem.setOrderPosition(position)
+            productItems.add(productItem)
         }
+
         return productItems
     }
 
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/update/UpdateOfferViewModel.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/update/UpdateOfferViewModel.groovy
index bc33dca09..1b1f4bcc2 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/update/UpdateOfferViewModel.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/offer/update/UpdateOfferViewModel.groovy
@@ -2,6 +2,7 @@ package life.qbic.portal.offermanager.components.offer.update
 
 import life.qbic.datamodel.dtos.business.Customer
 import life.qbic.datamodel.dtos.business.Offer
+import life.qbic.datamodel.dtos.business.ProductItem
 import life.qbic.datamodel.dtos.business.ProjectManager
 import life.qbic.datamodel.dtos.business.services.Product
 import life.qbic.datamodel.dtos.general.Person
@@ -10,6 +11,8 @@ import life.qbic.portal.offermanager.components.offer.create.CreateOfferViewMode
 import life.qbic.portal.offermanager.components.offer.create.ProductItemViewModel
 import life.qbic.portal.offermanager.dataresources.ResourcesService
 
+import java.util.stream.Collectors
+
 /**
  * Model with data for updating an existing offer.
  *
@@ -23,7 +26,7 @@ import life.qbic.portal.offermanager.dataresources.ResourcesService
  *
  * @since 1.0.0
  */
-class UpdateOfferViewModel extends CreateOfferViewModel{
+class UpdateOfferViewModel extends CreateOfferViewModel {
 
     final private EventEmitter<Offer> offerUpdate
 
@@ -50,8 +53,15 @@ class UpdateOfferViewModel extends CreateOfferViewModel{
         super.projectManager = offer.projectManager
         super.experimentalDesign = offer.experimentalDesign.orElse("")
         super.productItems.clear()
-        super.productItems.addAll(offer.items.collect {
-            new ProductItemViewModel(it.quantity, it.product)})
+
+        super.productItems.addAll(
+                offer.items.stream().sorted(new Comparator<ProductItem>() {
+                    @Override
+                    int compare(ProductItem o1, ProductItem o2) {
+                        return o1.offerPosition() - o2.offerPosition()
+                    }
+                }).map(productItem -> new ProductItemViewModel(productItem.quantity, productItem.product)).collect(Collectors.toList())
+        )
         super.savedOffer = Optional.of(offer)
         validateProjectInformation()
     }
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/person/update/UpdatePersonView.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/person/update/UpdatePersonView.groovy
index c4d0ce792..e69d1d026 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/person/update/UpdatePersonView.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/components/person/update/UpdatePersonView.groovy
@@ -1,8 +1,6 @@
 package life.qbic.portal.offermanager.components.person.update
 
-
 import com.vaadin.data.provider.ListDataProvider
-import com.vaadin.event.selection.SelectionListener
 import com.vaadin.icons.VaadinIcons
 import com.vaadin.shared.ui.grid.HeightMode
 import com.vaadin.ui.Button
diff --git a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/security/liferay/LiferayRoleService.groovy b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/security/liferay/LiferayRoleService.groovy
index 1f999d595..e4c3a70b5 100644
--- a/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/security/liferay/LiferayRoleService.groovy
+++ b/offer-manager-app/src/main/groovy/life/qbic/portal/offermanager/security/liferay/LiferayRoleService.groovy
@@ -1,10 +1,8 @@
 package life.qbic.portal.offermanager.security.liferay
 
 import com.liferay.portal.kernel.exception.PortalException
-import com.liferay.portal.model.User
 import com.liferay.portal.model.UserGroupRole
 import com.liferay.portal.service.UserGroupRoleLocalServiceUtil
-import com.liferay.portal.service.UserLocalServiceUtil
 import groovy.util.logging.Log4j2
 import life.qbic.portal.offermanager.security.Role
 import life.qbic.portal.offermanager.security.RoleService
diff --git a/offer-manager-app/src/main/webapp/VAADIN/themes/mytheme/mytheme.scss b/offer-manager-app/src/main/webapp/VAADIN/themes/mytheme/mytheme.scss
index 2431a6747..d5c0ab8b2 100644
--- a/offer-manager-app/src/main/webapp/VAADIN/themes/mytheme/mytheme.scss
+++ b/offer-manager-app/src/main/webapp/VAADIN/themes/mytheme/mytheme.scss
@@ -49,4 +49,12 @@
   .scrollable-layout {
     overflow: auto;
   }
+
+  .draggable-row-grab:hover {
+    cursor: grab;
+  }
+
+  .draggable-row-grab:active {
+    cursor: grabbing;
+  }
 }
diff --git a/offer-manager-app/src/main/webapp/WEB-INF/web.xml b/offer-manager-app/src/main/webapp/WEB-INF/web.xml
index d96d21667..db255a997 100644
--- a/offer-manager-app/src/main/webapp/WEB-INF/web.xml
+++ b/offer-manager-app/src/main/webapp/WEB-INF/web.xml
@@ -1,6 +1,5 @@
 <?xml version="1.0"?>
-<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
-http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
+<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
 	
 	<!-- Set to false only if you know what you are doing. -->
 	<!-- You don't know what you're doing but want to know? 
diff --git a/offer-manager-domain/src/main/groovy/life/qbic/business/RefactorConverter.java b/offer-manager-domain/src/main/groovy/life/qbic/business/RefactorConverter.java
index e07528cdc..ec5d7aaec 100644
--- a/offer-manager-domain/src/main/groovy/life/qbic/business/RefactorConverter.java
+++ b/offer-manager-domain/src/main/groovy/life/qbic/business/RefactorConverter.java
@@ -66,7 +66,8 @@ public static OfferV2 toOffer(life.qbic.datamodel.dtos.business.Offer offerDto)
     offer.setProjectObjective(offerDto.getProjectObjective());
     offer.setProjectTitle(offerDto.getProjectTitle());
     offer.setSelectedCustomerAffiliation(selectedCustomerAffiliation);
-    List<ProductItem> productItems = offerDto.getItems().stream().map(it -> toProductItem(offer, it))
+    List<ProductItem> productItems = offerDto.getItems().stream()
+        .map(it -> toProductItem(offer, it))
         .collect(Collectors.toList());
     offer.addItems(productItems);
 
@@ -74,7 +75,8 @@ public static OfferV2 toOffer(life.qbic.datamodel.dtos.business.Offer offerDto)
   }
 
   public static OfferItem toOfferItem(ProductItem productItem) {
-    String serviceProviderLabel = new FacilityFactory().getForString(productItem.getProduct().getServiceProvider())
+    String serviceProviderLabel = new FacilityFactory().getForString(
+            productItem.getProduct().getServiceProvider())
         .getLabel();
     return new OfferItem.Builder(
         productItem.getQuantity(),
@@ -130,6 +132,8 @@ public static ProductItem toProductItem(OfferV2 offer,
     double quantity = productItemDto.getQuantity();
     ProductItem productItem = new ProductItem(offer, product, quantity);
     productItem.setId(productItemDto.getId());
+    // Preserve offer position
+    productItem.setOfferPosition(productItemDto.offerPosition());
     return productItem;
   }
 
@@ -144,28 +148,35 @@ private static LocalDate toLocalDate(java.util.Date utilDate) {
         .toLocalDate();
   }
 
-  private static life.qbic.datamodel.dtos.business.ProductItem toProductItemDto(ProductItem productItem) {
+  private static life.qbic.datamodel.dtos.business.ProductItem toProductItemDto(
+      ProductItem productItem) {
     double quantity = productItem.getQuantity();
     life.qbic.datamodel.dtos.business.services.Product productDto = toProductDto(
         productItem.getProduct());
     double totalPrice = 0;
     double unitDiscount = 0;
-    return new life.qbic.datamodel.dtos.business.ProductItem(quantity,
+    life.qbic.datamodel.dtos.business.ProductItem itemDto = new life.qbic.datamodel.dtos.business.ProductItem(
+        quantity,
         productDto,
         totalPrice,
         unitDiscount);
+    itemDto.setOrderPosition(productItem.offerPosition());
+    return itemDto;
   }
 
-  public static ProductCategory toProductCategory(life.qbic.datamodel.dtos.business.ProductCategory category) {
+  public static ProductCategory toProductCategory(
+      life.qbic.datamodel.dtos.business.ProductCategory category) {
     return ProductCategory.forLabel(category.getValue());
   }
 
-  public static life.qbic.datamodel.dtos.business.ProjectManager toProjectManagerDto(Person person) {
+  public static life.qbic.datamodel.dtos.business.ProjectManager toProjectManagerDto(
+      Person person) {
     life.qbic.datamodel.dtos.business.ProjectManager.Builder projectManagerDtoBuilder = new life.qbic.datamodel.dtos.business.ProjectManager.Builder(
         person.getFirstName(),
         person.getLastName(),
         person.getEmail());
-    List<life.qbic.datamodel.dtos.business.Affiliation> personAffiliationsAsDto = person.getAffiliations().stream()
+    List<life.qbic.datamodel.dtos.business.Affiliation> personAffiliationsAsDto = person.getAffiliations()
+        .stream()
         .map(RefactorConverter::toAffiliationDto)
         .collect(Collectors.toList());
     projectManagerDtoBuilder.affiliations(personAffiliationsAsDto);
@@ -184,7 +195,8 @@ public static life.qbic.datamodel.dtos.business.Customer toCustomerDto(Person pe
         person.getFirstName(),
         person.getLastName(),
         person.getEmail());
-    List<life.qbic.datamodel.dtos.business.Affiliation> personAffiliationsAsDto = person.getAffiliations().stream()
+    List<life.qbic.datamodel.dtos.business.Affiliation> personAffiliationsAsDto = person.getAffiliations()
+        .stream()
         .map(RefactorConverter::toAffiliationDto)
         .collect(Collectors.toList());
     customerBuilder.affiliations(personAffiliationsAsDto);
@@ -202,7 +214,8 @@ public static Person toPerson(life.qbic.datamodel.dtos.general.Person personDto)
     String emailAddress = personDto.getEmailAddress();
     String firstName = personDto.getFirstName();
     String lastName = personDto.getLastName();
-    String title = personDto.getTitle() != AcademicTitle.NONE ? personDto.getTitle().getValue() : "";
+    String title =
+        personDto.getTitle() != AcademicTitle.NONE ? personDto.getTitle().getValue() : "";
     List<Affiliation> affiliations = personDto.getAffiliations().stream()
         .map(RefactorConverter::toAffiliation)
         .collect(Collectors.toList());
@@ -237,7 +250,8 @@ public static life.qbic.datamodel.dtos.general.Person toPersonDTO(Person person)
   }
 
 
-  public static life.qbic.datamodel.dtos.business.Affiliation toAffiliationDto(Affiliation affiliation) {
+  public static life.qbic.datamodel.dtos.business.Affiliation toAffiliationDto(
+      Affiliation affiliation) {
     life.qbic.datamodel.dtos.business.Affiliation.Builder affiliationDtoBuilder =
         new life.qbic.datamodel.dtos.business.Affiliation.Builder(
             affiliation.getOrganization(),
@@ -268,7 +282,8 @@ public static Affiliation toAffiliation(
     return affiliation;
   }
 
-  static life.qbic.datamodel.dtos.business.AffiliationCategory toAffiliationCategoryDto(AffiliationCategory affiliationCategory) {
+  static life.qbic.datamodel.dtos.business.AffiliationCategory toAffiliationCategoryDto(
+      AffiliationCategory affiliationCategory) {
     switch (affiliationCategory) {
       case INTERNAL:
         return life.qbic.datamodel.dtos.business.AffiliationCategory.INTERNAL;
@@ -372,7 +387,8 @@ public static life.qbic.datamodel.dtos.business.services.Product toProductDto(Pr
           externalUnitPrice,
           productUnit, runningNumber, serviceProvider);
     } else if (DataStorage.class.equals(requestedProductClass)) {
-      return new DataStorage(id, productName, productDescription, internalUnitPrice, externalUnitPrice,
+      return new DataStorage(id, productName, productDescription, internalUnitPrice,
+          externalUnitPrice,
           productUnit, runningNumber, serviceProvider);
     } else if (ExternalServiceProduct.class.equals(requestedProductClass)) {
       return new ExternalServiceProduct(id, productName, productDescription, internalUnitPrice,
@@ -462,7 +478,8 @@ protected static class ProductCategoryParser implements
      * @return the function result
      */
     @Override
-    public Class<? extends life.qbic.datamodel.dtos.business.services.Product> apply(String categoryName) {
+    public Class<? extends life.qbic.datamodel.dtos.business.services.Product> apply(
+        String categoryName) {
       return productCategoryMap().entrySet().stream()
           .filter(it -> it.getValue().equalsIgnoreCase(categoryName))
           .map(Entry::getKey)
@@ -472,8 +489,10 @@ public Class<? extends life.qbic.datamodel.dtos.business.services.Product> apply
           );
     }
   }
+
   protected static class ProductCategoryFormatter implements
       Function<Class<? extends life.qbic.datamodel.dtos.business.services.Product>, String> {
+
     /**
      * Applies this function to the given argument.
      *
diff --git a/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferChecksumSupplier.java b/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferChecksumSupplier.java
index eb8900e8a..42c312b85 100644
--- a/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferChecksumSupplier.java
+++ b/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferChecksumSupplier.java
@@ -5,6 +5,7 @@
 import java.security.NoSuchAlgorithmException;
 import java.util.Optional;
 import java.util.function.Supplier;
+import java.util.stream.Collectors;
 import life.qbic.business.persons.affiliation.Affiliation;
 import life.qbic.business.products.ProductItem;
 
@@ -52,6 +53,7 @@ private MessageDigest update(MessageDigest digest) {
         .map(this::updateWithCustomer)
         .map(this::updateWithProjectManager)
         .map(this::updateWithSelectedAffiliation)
+        .map(this::updateWithItemOrder)
         .orElseThrow(() -> new RuntimeException("Unexpected error updating offer checksum."));
   }
 
@@ -72,6 +74,12 @@ private MessageDigest updateWithExperimentalDesignIfPresent(MessageDigest digest
     return digest;
   }
 
+  private MessageDigest updateWithItemOrder(MessageDigest digest) {
+    digest.update(offer.getItems().stream().map(ProductItem::offerPosition).map(String::valueOf)
+        .collect(Collectors.joining()).getBytes(StandardCharsets.UTF_8));
+    return digest;
+  }
+
   private MessageDigest updateWithProductItems(MessageDigest digest) {
     offer.getItems().forEach(it -> updateWithProductItem(digest, it));
     return digest;
@@ -90,7 +98,8 @@ private MessageDigest updateWithProjectManager(MessageDigest digest) {
   private MessageDigest updateWithSelectedAffiliation(MessageDigest digest) {
     Affiliation selectedCustomerAffiliation = offer.getSelectedCustomerAffiliation();
     digest.update(selectedCustomerAffiliation.getOrganization().getBytes(StandardCharsets.UTF_8));
-    digest.update(selectedCustomerAffiliation.getAddressAddition().getBytes(StandardCharsets.UTF_8));
+    digest.update(
+        selectedCustomerAffiliation.getAddressAddition().getBytes(StandardCharsets.UTF_8));
     digest.update(selectedCustomerAffiliation.getStreet().getBytes(StandardCharsets.UTF_8));
     return digest;
   }
diff --git a/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferContent.groovy b/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferContent.groovy
index 435587fee..81381d57f 100644
--- a/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferContent.groovy
+++ b/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferContent.groovy
@@ -169,7 +169,12 @@ class OfferContent {
      * @return
      */
     List<OfferItem> getDataGenerationItems() {
-        return dataGenerationItems.collect()
+        return dataGenerationItems.stream().sorted(new Comparator<OfferItem>() {
+            @Override
+            int compare(OfferItem o1, OfferItem o2) {
+                return o1.position - o2.position
+            }
+        }).collect()
     }
 
     /**
@@ -177,7 +182,12 @@ class OfferContent {
      * @return
      */
     List<OfferItem> getDataAnalysisItems() {
-        return dataAnalysisItems.collect()
+        return dataAnalysisItems.stream().sorted(new Comparator<OfferItem>() {
+            @Override
+            int compare(OfferItem o1, OfferItem o2) {
+                return o1.position - o2.position
+            }
+        }).collect()
     }
 
     /**
@@ -185,7 +195,12 @@ class OfferContent {
      * @return
      */
     List<OfferItem> getDataManagementItems() {
-        return dataManagementItems.collect()
+        return dataManagementItems.stream().sorted(new Comparator<OfferItem>() {
+            @Override
+            int compare(OfferItem o1, OfferItem o2) {
+                return o1.position - o2.position
+            }
+        }).collect()
     }
 
     /**
@@ -193,7 +208,12 @@ class OfferContent {
      * @return
      */
     List<OfferItem> getExternalServiceItems() {
-        return externalServiceItems.collect()
+        return externalServiceItems.stream().sorted(new Comparator<OfferItem>() {
+            @Override
+            int compare(OfferItem o1, OfferItem o2) {
+                return o1.position - o2.position
+            }
+        }).collect()
     }
 
     OfferContent(String customerFirstName, String customerLastName, String customerTitle, String customerOrganisation, String customerAddressAddition, String customerStreet, String customerPostalCode, String customerCity, String customerCountry, String projectManagerFirstName, String projectManagerLastName, String projectManagerTitle, String projectManagerEmail, String projectManagerOrganisation, String projectManagerStreet, String projectManagerPostalCode, String projectManagerCity, String projectManagerCountry, Date creationDate, Date expirationDate, String projectTitle, String projectObjective, String experimentalDesign, String offerIdentifier, List<OfferItem> dataGenerationItems, List<OfferItem> dataAnalysisItems, List<OfferItem> dataManagementItems, List<OfferItem> externalServiceItems, double overheadTotal, double overheadRatio, double overheadsDataGeneration, double overheadsDataAnalysis, double overheadsProjectManagementAndDataStorage, double overheadsExternalService, double netDataGeneration, double netDataAnalysis, double netPMandDS, double netExternalServices, double totalCost, double netCost, double netCostsWithOverheads, double totalVat, double vatRatio, Double totalDiscountAmount) {
diff --git a/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferItem.groovy b/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferItem.groovy
index 806a8ddaf..29dd0a3be 100644
--- a/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferItem.groovy
+++ b/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferItem.groovy
@@ -26,6 +26,7 @@ class OfferItem {
     final double listPrice
     final double itemNet
     final String category
+    final int position
 
     static class Builder {
         final double quantity
@@ -39,6 +40,7 @@ class OfferItem {
         final String unit
         final double listPrice
         final double itemNet
+        int position = -1
         String category
 
         /**
@@ -77,6 +79,11 @@ class OfferItem {
             return this
         }
 
+        Builder setPosition(int position) {
+            this.position = position
+            return this
+        }
+
         OfferItem build() {
             return new OfferItem(this)
         }
@@ -99,5 +106,6 @@ class OfferItem {
         this.listPrice = builder.listPrice
         this.itemNet = builder.itemNet
         this.category = builder.category ? builder.category : ""
+        this.position = builder.position
     }
 }
diff --git a/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferV2.groovy b/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferV2.groovy
index cbdb2ddd7..612e25098 100644
--- a/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferV2.groovy
+++ b/offer-manager-domain/src/main/groovy/life/qbic/business/offers/OfferV2.groovy
@@ -30,592 +30,608 @@ import java.time.LocalDate
 @Table(name = "offers")
 class OfferV2 {
 
-  @Id
-  @GeneratedValue(strategy = GenerationType.IDENTITY)
-  @Column(name = "id")
-  private int id
-
-  /**
-   * Date on which the offer was lastly modified
-   */
-  @Column(name = "creationDate")
-  private LocalDate creationDate = LocalDate.now()
-
-  /**
-   * The date on which the offer expires
-   */
-  @Column(name = "expirationDate")
-  private LocalDate expirationDate
-
-  /**
-   * The customer for which this offer was created
-   */
-  @OneToOne(cascade = [CascadeType.DETACH, CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH])
-  @JoinColumn(name = "customerId")
-  private Person customer
-
-  /**
-   * The QBiC project manager who was assigned to the project
-   */
-  @OneToOne(cascade = [CascadeType.DETACH, CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH])
-  @JoinColumn(name = "projectManagerId")
-  private Person projectManager
-
-  /**
-   * The title of the project
-   */
-  @Column(name = "projectTitle")
-  private String projectTitle
-
-  /**
-   * A short objective of the project
-   */
-  @Column(name = "projectObjective")
-  private String projectObjective
-
-  /**
-   * A short description of the experimental design of the project
-   */
-  @Column(name = "experimentalDesign")
-  @Convert(converter = OptionalStringConverter.class)
-  private Optional<String> experimentalDesign
-
-  /**
-   * A list of items for which the customer will be charged
-   */
-  @OneToMany(mappedBy = "offer", cascade = CascadeType.ALL)
-  private List<ProductItem> items = []
-
-  @Column(name = "offerId")
-  private String offerId
-
-  /**
-   * The affiliation of the customer selected for this offer
-   */
-  @OneToOne(cascade = [CascadeType.DETACH, CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH])
-  @JoinColumn(name = "customerAffiliationId")
-  private Affiliation selectedCustomerAffiliation
-
-  /**
-   * Holds the determined overhead total derived from the
-   * customer's affiliation.
-   */
-  @Column(name = "overheads")
-  private double overhead
-
-  /**
-   * The overhead ratio that is applied to calculate the total offer price. The ratio is chosen
-   * based on the customer's affiliation.
-   *  e.g. 0.4 or a 40% markup for external customers
-   */
-  @Transient
-  private double overheadRatio
-
-
-  //Note Currently all offer checksums are updated during the offerOverview loading process
-  @Column(name = "checksum")
-  @Access(AccessType.PROPERTY)
-  private String checksum
-
-  /**
-   * A project that has been created from this offer (optional)
-   */
-  @Column(name = "associatedProject")
-  @Convert(converter = OptionalProjectIdentifierConverter.class)
-  private ProjectIdentifier associatedProject
-
-  @Transient
-  private ItemGroup dataGenerationItems = new ItemGroup()
-  @Transient
-  private ItemGroup dataAnalysisItems = new ItemGroup()
-  @Transient
-  private ItemGroup dataManagementItems = new ItemGroup()
-  @Transient
-  private ItemGroup externalServiceItems = new ItemGroup()
-
-  @Transient private BigDecimal dataAnalysisOverhead = BigDecimal.ZERO
-  @Transient private BigDecimal dataGenerationOverhead = BigDecimal.ZERO
-  @Transient private BigDecimal dataManagementOverhead = BigDecimal.ZERO
-  @Transient private BigDecimal externalServiceOverhead = BigDecimal.ZERO
-  @Transient private BigDecimal dataAnalysisSalePrice = BigDecimal.ZERO
-  @Transient private BigDecimal dataGenerationSalePrice = BigDecimal.ZERO
-  @Transient private BigDecimal dataManagementSalePrice = BigDecimal.ZERO
-  @Transient private BigDecimal externalServiceSalePrice = BigDecimal.ZERO
-  @Transient private BigDecimal salePrice = BigDecimal.ZERO
-  @Transient private BigDecimal vatRatio = BigDecimal.ZERO
-  @Transient private BigDecimal priceAfterTax = BigDecimal.ZERO
-  @Transient private BigDecimal taxAmount = BigDecimal.ZERO
-  @Transient private BigDecimal priceBeforeTax = BigDecimal.ZERO
-  @Transient private BigDecimal discountAmount = BigDecimal.ZERO
-
-  OfferV2() {}
-
-  void setPersistentId(int id) {
-    this.id = id
-  }
-
-  int getPersistentId() {
-    return this.id
-  }
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "id")
+    private int id
+
+    /**
+     * Date on which the offer was lastly modified
+     */
+    @Column(name = "creationDate")
+    private LocalDate creationDate = LocalDate.now()
+
+    /**
+     * The date on which the offer expires
+     */
+    @Column(name = "expirationDate")
+    private LocalDate expirationDate
+
+    /**
+     * The customer for which this offer was created
+     */
+    @OneToOne(cascade = [CascadeType.DETACH, CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH])
+    @JoinColumn(name = "customerId")
+    private Person customer
+
+    /**
+     * The QBiC project manager who was assigned to the project
+     */
+    @OneToOne(cascade = [CascadeType.DETACH, CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH])
+    @JoinColumn(name = "projectManagerId")
+    private Person projectManager
+
+    /**
+     * The title of the project
+     */
+    @Column(name = "projectTitle")
+    private String projectTitle
+
+    /**
+     * A short objective of the project
+     */
+    @Column(name = "projectObjective")
+    private String projectObjective
+
+    /**
+     * A short description of the experimental design of the project
+     */
+    @Column(name = "experimentalDesign")
+    @Convert(converter = OptionalStringConverter.class)
+    private Optional<String> experimentalDesign
+
+    /**
+     * A list of items for which the customer will be charged
+     */
+    @OneToMany(mappedBy = "offer", cascade = CascadeType.ALL)
+    private List<ProductItem> items = []
+
+    @Column(name = "offerId")
+    private String offerId
+
+    /**
+     * The affiliation of the customer selected for this offer
+     */
+    @OneToOne(cascade = [CascadeType.DETACH, CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH])
+    @JoinColumn(name = "customerAffiliationId")
+    private Affiliation selectedCustomerAffiliation
+
+    /**
+     * Holds the determined overhead total derived from the
+     * customer's affiliation.
+     */
+    @Column(name = "overheads")
+    private double overhead
+
+    /**
+     * The overhead ratio that is applied to calculate the total offer price. The ratio is chosen
+     * based on the customer's affiliation.
+     *  e.g. 0.4 or a 40% markup for external customers
+     */
+    @Transient
+    private double overheadRatio
+
+
+    //Note Currently all offer checksums are updated during the offerOverview loading process
+    @Column(name = "checksum")
+    @Access(AccessType.PROPERTY)
+    private String checksum
+
+    /**
+     * A project that has been created from this offer (optional)
+     */
+    @Column(name = "associatedProject")
+    @Convert(converter = OptionalProjectIdentifierConverter.class)
+    private ProjectIdentifier associatedProject
+
+    @Transient
+    private ItemGroup dataGenerationItems = new ItemGroup()
+    @Transient
+    private ItemGroup dataAnalysisItems = new ItemGroup()
+    @Transient
+    private ItemGroup dataManagementItems = new ItemGroup()
+    @Transient
+    private ItemGroup externalServiceItems = new ItemGroup()
+
+    @Transient
+    private BigDecimal dataAnalysisOverhead = BigDecimal.ZERO
+    @Transient
+    private BigDecimal dataGenerationOverhead = BigDecimal.ZERO
+    @Transient
+    private BigDecimal dataManagementOverhead = BigDecimal.ZERO
+    @Transient
+    private BigDecimal externalServiceOverhead = BigDecimal.ZERO
+    @Transient
+    private BigDecimal dataAnalysisSalePrice = BigDecimal.ZERO
+    @Transient
+    private BigDecimal dataGenerationSalePrice = BigDecimal.ZERO
+    @Transient
+    private BigDecimal dataManagementSalePrice = BigDecimal.ZERO
+    @Transient
+    private BigDecimal externalServiceSalePrice = BigDecimal.ZERO
+    @Transient
+    private BigDecimal salePrice = BigDecimal.ZERO
+    @Transient
+    private BigDecimal vatRatio = BigDecimal.ZERO
+    @Transient
+    private BigDecimal priceAfterTax = BigDecimal.ZERO
+    @Transient
+    private BigDecimal taxAmount = BigDecimal.ZERO
+    @Transient
+    private BigDecimal priceBeforeTax = BigDecimal.ZERO
+    @Transient
+    private BigDecimal discountAmount = BigDecimal.ZERO
+
+    OfferV2() {}
+
+    void setPersistentId(int id) {
+        this.id = id
+    }
+
+    int getPersistentId() {
+        return this.id
+    }
 /**
-   * Constructor for an OfferV2 entity on which price calculation can be performed on.
-   * @param items
-   * @param selectedCustomerAffiliation
-   */
-  OfferV2(Affiliation selectedCustomerAffiliation, OfferId identifier) {
-    this.setSelectedCustomerAffiliation(selectedCustomerAffiliation)
-    this.identifier = identifier
-  }
-
-  /**
-   * Adds the item to the corresponding item group based on the product category.
-   * @param item the added item
-   */
-  private void addItemToGroup(ProductItem item) {
-    List<String> dataGenerationCategories = Arrays.asList("Sequencing", "Proteomics", "Metabolomics")
-    List<String> dataAnalysisCategories = Arrays.asList("Primary Bioinformatics", "Secondary Bioinformatics")
-    List<String> projectManagementCategories = Arrays.asList("Project Management", "Data Storage")
-    List<String> externalServiceCategories = Collections.singletonList("External Service")
-
-    String category = item.getProduct().getCategory()
-    if (dataGenerationCategories.contains(category)) {
-      this.dataGenerationItems.add(item)
-    } else if (dataAnalysisCategories.contains(category)) {
-      this.dataAnalysisItems.add(item)
-    } else if (projectManagementCategories.contains(category)) {
-      this.dataManagementItems.add(item)
-    } else if (externalServiceCategories.contains(category)) {
-      this.externalServiceItems.add(item)
-    }
-  }
-
-  /**
-   * Determines the VAT ratio. The VAT ratio for Germany is 0.19. For all
-   * other countries, the VAT ratio is 0.
-   *
-   * @param country the country for which to get the VAT ratio
-   * @return the VAT ratio for the provided country
-   */
-  protected static BigDecimal vatRatio(String country) {
-    Map<String, BigDecimal> vatRatios = new HashMap<>()
-    vatRatios.put("Germany", BigDecimal.valueOf(0.19))
-    return vatRatios.getOrDefault(country, BigDecimal.ZERO)
-  }
-
-  BigDecimal getPriceAfterTax() {
-    return priceAfterTax
-  }
-
-  BigDecimal getTaxAmount() {
-    return taxAmount
-  }
-
-  BigDecimal getPriceBeforeTax() {
-    return priceBeforeTax
-  }
-
-  protected void setChecksum(String checksum) {
-    this.checksum = checksum
-  }
-
-  /**
-   * Thread-safe request of the current offer content's SHA-256 checksum
-   * @return the checksum at the time of request execution
-   */
-  String getChecksum() {
-    synchronized (this) {
-      return checksum = new OfferChecksumSupplier(this).get()
-    }
-  }
-
-  BigDecimal getDataAnalysisOverhead() {
-    return dataAnalysisOverhead
-  }
-
-  BigDecimal getDataGenerationOverhead() {
-    return dataGenerationOverhead
-  }
-
-  BigDecimal getDataManagementOverhead() {
-    return dataManagementOverhead
-  }
-
-  BigDecimal getExternalServiceOverhead() {
-    return externalServiceOverhead
-  }
-
-  BigDecimal getDataAnalysisSalePrice() {
-    return dataAnalysisSalePrice
-  }
-
-  BigDecimal getDataGenerationSalePrice() {
-    return dataGenerationSalePrice
-  }
-
-  BigDecimal getDataManagementSalePrice() {
-    return dataManagementSalePrice
-  }
-
-  BigDecimal getExternalServiceSalePrice() {
-    return externalServiceSalePrice
-  }
-
-  BigDecimal getSalePrice() {
-    return salePrice
-  }
-
-  BigDecimal getVatRatio() {
-    return vatRatio
-  }
-
-  BigDecimal getTotalDiscountAmount() {
-    return discountAmount
-  }
-
-  LocalDate getCreationDate() {
-    return creationDate
-  }
-
-  void setCreationDate(LocalDate creationDate) {
-    this.creationDate = creationDate
-    expireNinetyDaysAfterCreation()
-  }
-
-  LocalDate getExpirationDate() {
-    return expirationDate
-  }
-
-  void setExpirationDate(LocalDate expirationDate) {
-    this.expirationDate = expirationDate
-  }
-
-  Person getCustomer() {
-    return customer
-  }
-
-  void setCustomer(Person customer) {
-    this.customer = customer
-  }
-
-  Person getProjectManager() {
-    return projectManager
-  }
-
-  void setProjectManager(Person projectManager) {
-    this.projectManager = projectManager
-  }
-
-  String getProjectTitle() {
-    return projectTitle
-  }
-
-  void setProjectTitle(String projectTitle) {
-    this.projectTitle = projectTitle
-  }
-
-  String getProjectObjective() {
-    return projectObjective
-  }
-
-  void setProjectObjective(String projectObjective) {
-    this.projectObjective = projectObjective
-  }
-
-  Optional<String> getExperimentalDesign() {
-    return experimentalDesign
-  }
-
-  void setExperimentalDesign(Optional<String> experimentalDesign) {
-    this.experimentalDesign = experimentalDesign
-  }
-
-  OfferId getIdentifier() {
-    return OfferId.from(offerId)
-  }
-
-  void setIdentifier(OfferId identifier) {
-    this.offerId = identifier.toString()
-  }
-
-  Affiliation getSelectedCustomerAffiliation() {
-    return selectedCustomerAffiliation
-  }
-
-  void setSelectedCustomerAffiliation(Affiliation selectedCustomerAffiliation) {
-    this.selectedCustomerAffiliation = selectedCustomerAffiliation
-    recomputeWithAffiliation()
-  }
-
-  private void recomputeWithAffiliation() {
-    aggregateCosts()
-  }
-
-  private void updateVatRatio() {
-    this.vatRatio = vatRatio(selectedCustomerAffiliation.country)
-  }
-
-  private void updatePriceBeforeTax() {
-    this.priceBeforeTax = BigDecimal.valueOf(overhead).add(salePrice)
-  }
-
-  private void updateOverheadAmount() {
-    this.dataGenerationOverhead = dataGenerationSalePrice * overheadRatio
-    this.dataAnalysisOverhead = dataAnalysisSalePrice * overheadRatio
-    this.dataManagementOverhead = dataManagementSalePrice * overheadRatio
-    this.externalServiceOverhead = externalServiceSalePrice * overheadRatio
-    this.overhead = dataGenerationOverhead
-            .add(dataAnalysisOverhead)
-            .add(dataManagementOverhead)
-            .add(externalServiceOverhead)
-  }
-
-  double getOverhead() {
-    return BigDecimal.valueOf(overhead).doubleValue()
-  }
-
-  protected void setOverhead(double overhead) {
-    this.overhead = overhead
-  }
-
-  double getOverheadRatio() {
-    return overheadRatio
-  }
-
-  Optional<ProjectIdentifier> getAssociatedProject() {
-    return Optional.ofNullable(associatedProject)
-  }
-
-  void setAssociatedProject(ProjectIdentifier associatedProject) {
-    this.associatedProject = associatedProject
-  }
-
-  List<ProductItem> getItems() {
-    return items.collect()
-  }
-
-  void setItems(List<ProductItem> items) {
-    clearItems()
-    addItems(items)
-  }
-
-  private void clearItems() {
-    items.clear()
-    dataManagementItems.clear()
-    dataAnalysisItems.clear()
-    dataGenerationItems.clear()
-    externalServiceItems.clear()
-  }
-
-  void addItems(List<ProductItem> items) {
-    items.forEach(it -> addItem(it.getProduct(), it.getQuantity()))
-    aggregateCosts()
-  }
-
-  private void aggregateCosts() {
-    //ATTENTION: TEMPORAL COUPLING! Do not change the order
-    updateSalePrices()
-    //-
-    updateOverhead()
-    updatePriceBeforeTax()
-    updateVat()
-    updatePriceAfterTax()
-    //-
-    updateDiscountAmount()
-  }
-
-  private void updateVat() {
-    TaxPolicy taxPolicy = TaxOffice.policyFor(selectedCustomerAffiliation.category, selectedCustomerAffiliation.country)
-    vatRatio = taxPolicy.getVatRatio()
-    taxAmount = taxPolicy.calculateTaxes(priceBeforeTax).setScale(2, RoundingMode.HALF_UP)
-  }
-
-  private void updateOverhead() {
-    updateOverheadRatio()
-    updateOverheadAmount()
-  }
-
-  private void updatePriceAfterTax() {
-    this.priceAfterTax = priceBeforeTax.add(taxAmount)
-  }
-
-  /**
-   * This method does not recompute the prices! For internal use only!
-   * @param product the product for which an item shall be added
-   * @param quantity the amount of the product
-   */
-  private void addItem(Product product, Double quantity) {
-    ProductItem productItem = new ProductItem(this, product, quantity)
-    this.addItemToGroup(productItem)
-    this.items.add(productItem)
-  }
-
-  /**
-   * This method is executed after loading the offer from the database.
-   * It is responsible to update all the prices
-   */
-  @PostLoad
-  protected void onPostLoad() {
-    loadFields()
-    items.forEach(ProductItem::refresh)
-    items.forEach(this::addItemToGroup)
-    aggregateCosts()
-    expireNinetyDaysAfterCreation()
-  }
-
-  private void loadFields() {
-    getItems()
-    getAssociatedProject()
-  }
-
-  private void updateSalePrices() {
-    dataGenerationSalePrice = dataGenerationItems.getSalePrice()
-    dataAnalysisSalePrice = dataAnalysisItems.getSalePrice()
-    dataManagementSalePrice = dataManagementItems.getSalePrice()
-    externalServiceSalePrice = externalServiceItems.getSalePrice()
-    salePrice = dataGenerationSalePrice
-            .add(dataAnalysisSalePrice)
-            .add(dataManagementSalePrice)
-            .add(externalServiceSalePrice)
-  }
-
-
-  List<ProductItem> getDataManagementItems() {
-    // Create a copy of the item collection
-    return dataManagementItems.iterator().collect()
-  }
-
-  List<ProductItem> getDataAnalysisItems() {
-    return dataAnalysisItems.iterator().collect()
-  }
-
-  List<ProductItem> getDataGenerationItems() {
-    return dataGenerationItems.iterator().collect()
-  }
-
-  List<ProductItem> getExternalServiceItems() {
-    return externalServiceItems.iterator().collect()
-  }
-
-  static OfferV2 copyOf(OfferV2 original) {
-    return original.copy()
-  }
-
-  private OfferV2 copy() {
-    OfferV2 offerCopy = new OfferV2()
-
-    //sorted alphabetically
-    offerCopy.setAssociatedProject(this.getAssociatedProject()?.orElse(null))
-    offerCopy.setCreationDate(this.getCreationDate())
-    offerCopy.setCustomer(this.getCustomer())
-    offerCopy.setExperimentalDesign(this.getExperimentalDesign())
-    offerCopy.setExpirationDate(this.getExpirationDate())
-    offerCopy.setIdentifier(this.getIdentifier())
-    offerCopy.setProjectManager(this.getProjectManager())
-    offerCopy.setProjectObjective(this.getProjectObjective())
-    offerCopy.setProjectTitle(this.getProjectTitle())
-    offerCopy.setSelectedCustomerAffiliation(this.getSelectedCustomerAffiliation())
-
-    //fields
-    offerCopy.setItems(this.getItems())
-
-    return offerCopy
-  }
-
-  /**
-   * Updates the overhead ratio and any price depending on it
-   * <ul>
-   *   <li>overhead costs</li>
-   *   <li>price before tax</li>
-   *   <li>tax amount</li>
-   *   <li>price after tax</li>
-   * </ul>
-   */
-  private void updateOverheadRatio() {
-    def category = selectedCustomerAffiliation.getCategory()
-    this.overheadRatio = determineOverheadRate(category)
-  }
-
-  private static BigDecimal determineOverheadRate(AffiliationCategory category) {
-    if (category == AffiliationCategory.INTERNAL) {
-      return BigDecimal.ZERO
-    }
-    if (category == AffiliationCategory.EXTERNAL_ACADEMIC) {
-      return new BigDecimal("0.2")
-    }
-    return new BigDecimal("0.4")
-  }
-  //Note this is only used for Reporting and not in the offer
-  private void updateDiscountAmount() {
-    this.discountAmount = dataGenerationItems.discountAmount
-            .add(dataAnalysisItems.discountAmount)
-            .add(dataManagementItems.discountAmount)
-            .add(externalServiceItems.discountAmount)
-  }
-
-  private void expireNinetyDaysAfterCreation() {
-    expirationDate = creationDate.plusDays(90)
-  }
-
-  private static class ItemGroup extends ArrayList<ProductItem> {
+ * Constructor for an OfferV2 entity on which price calculation can be performed on.
+ * @param items
+ * @param selectedCustomerAffiliation
+ */
+    OfferV2(Affiliation selectedCustomerAffiliation, OfferId identifier) {
+        this.setSelectedCustomerAffiliation(selectedCustomerAffiliation)
+        this.identifier = identifier
+    }
+
+    /**
+     * Adds the item to the corresponding item group based on the product category.
+     * @param item the added item
+     */
+    private void addItemToGroup(ProductItem item) {
+        List<String> dataGenerationCategories = Arrays.asList("Sequencing", "Proteomics", "Metabolomics")
+        List<String> dataAnalysisCategories = Arrays.asList("Primary Bioinformatics", "Secondary Bioinformatics")
+        List<String> projectManagementCategories = Arrays.asList("Project Management", "Data Storage")
+        List<String> externalServiceCategories = Collections.singletonList("External Service")
+
+        String category = item.getProduct().getCategory()
+        if (dataGenerationCategories.contains(category)) {
+            this.dataGenerationItems.add(item)
+        } else if (dataAnalysisCategories.contains(category)) {
+            this.dataAnalysisItems.add(item)
+        } else if (projectManagementCategories.contains(category)) {
+            this.dataManagementItems.add(item)
+        } else if (externalServiceCategories.contains(category)) {
+            this.externalServiceItems.add(item)
+        }
+    }
+
+    /**
+     * Determines the VAT ratio. The VAT ratio for Germany is 0.19. For all
+     * other countries, the VAT ratio is 0.
+     *
+     * @param country the country for which to get the VAT ratio
+     * @return the VAT ratio for the provided country
+     */
+    protected static BigDecimal vatRatio(String country) {
+        Map<String, BigDecimal> vatRatios = new HashMap<>()
+        vatRatios.put("Germany", BigDecimal.valueOf(0.19))
+        return vatRatios.getOrDefault(country, BigDecimal.ZERO)
+    }
+
+    BigDecimal getPriceAfterTax() {
+        return priceAfterTax
+    }
+
+    BigDecimal getTaxAmount() {
+        return taxAmount
+    }
+
+    BigDecimal getPriceBeforeTax() {
+        return priceBeforeTax
+    }
+
+    protected void setChecksum(String checksum) {
+        this.checksum = checksum
+    }
+
+    /**
+     * Thread-safe request of the current offer content's SHA-256 checksum
+     * @return the checksum at the time of request execution
+     */
+    String getChecksum() {
+        synchronized (this) {
+            return checksum = new OfferChecksumSupplier(this).get()
+        }
+    }
+
+    BigDecimal getDataAnalysisOverhead() {
+        return dataAnalysisOverhead
+    }
+
+    BigDecimal getDataGenerationOverhead() {
+        return dataGenerationOverhead
+    }
+
+    BigDecimal getDataManagementOverhead() {
+        return dataManagementOverhead
+    }
+
+    BigDecimal getExternalServiceOverhead() {
+        return externalServiceOverhead
+    }
+
+    BigDecimal getDataAnalysisSalePrice() {
+        return dataAnalysisSalePrice
+    }
+
+    BigDecimal getDataGenerationSalePrice() {
+        return dataGenerationSalePrice
+    }
+
+    BigDecimal getDataManagementSalePrice() {
+        return dataManagementSalePrice
+    }
+
+    BigDecimal getExternalServiceSalePrice() {
+        return externalServiceSalePrice
+    }
+
     BigDecimal getSalePrice() {
-      this.stream().map(ProductItem::getSalePrice).reduce(BigDecimal.ZERO, BigDecimal::add)
+        return salePrice
+    }
+
+    BigDecimal getVatRatio() {
+        return vatRatio
+    }
+
+    BigDecimal getTotalDiscountAmount() {
+        return discountAmount
     }
 
-    BigDecimal getDiscountAmount() {
-      return this.stream().map(ProductItem::getDiscountAmount).reduce(BigDecimal.ZERO, BigDecimal::add)
+    LocalDate getCreationDate() {
+        return creationDate
     }
-  }
 
+    void setCreationDate(LocalDate creationDate) {
+        this.creationDate = creationDate
+        expireNinetyDaysAfterCreation()
+    }
 
-  private static class OptionalStringConverter implements AttributeConverter<Optional<String>, String> {
+    LocalDate getExpirationDate() {
+        return expirationDate
+    }
 
-    @Override
-    String convertToDatabaseColumn(Optional<String> s) {
-      return s.orElse("")
+    void setExpirationDate(LocalDate expirationDate) {
+        this.expirationDate = expirationDate
     }
 
-    @Override
-    Optional<String> convertToEntityAttribute(String s) {
-      // If the String is null or empty, we return an empty Optional
-      return s ? Optional.of(s) : Optional.empty() as Optional<String>
+    Person getCustomer() {
+        return customer
     }
-  }
 
-  private static class OptionalProjectIdentifierConverter implements AttributeConverter<ProjectIdentifier, String> {
+    void setCustomer(Person customer) {
+        this.customer = customer
+    }
+
+    Person getProjectManager() {
+        return projectManager
+    }
 
-    @Override
-    String convertToDatabaseColumn(ProjectIdentifier projectIdentifier) {
-      if (projectIdentifier) {
-        return projectIdentifier.toString()
-      } else {
-        return null
-      }
+    void setProjectManager(Person projectManager) {
+        this.projectManager = projectManager
     }
 
-    @Override
-    ProjectIdentifier convertToEntityAttribute(String projectIdentifier) {
-      ProjectIdentifier identifier = null
-      if (!projectIdentifier) {
-        return identifier
-      }
-      try {
-        /*
-        A full openBIS project ID has the format: '/<space>/<project>', where
-        <space> and <project> are placeholders for real space and project names.
-         */
-        def splittedIdentifier = projectIdentifier.split("/")
-        if (splittedIdentifier.length != 3) {
-          throw new RuntimeException(
-                  "Project identifier has an unexpected number of separators: ${projectIdentifier}. " +
-                          "The expected format must follow this schema: \'/<space>/<project>\'")
+    String getProjectTitle() {
+        return projectTitle
+    }
+
+    void setProjectTitle(String projectTitle) {
+        this.projectTitle = projectTitle
+    }
+
+    String getProjectObjective() {
+        return projectObjective
+    }
+
+    void setProjectObjective(String projectObjective) {
+        this.projectObjective = projectObjective
+    }
+
+    Optional<String> getExperimentalDesign() {
+        return experimentalDesign
+    }
+
+    void setExperimentalDesign(Optional<String> experimentalDesign) {
+        this.experimentalDesign = experimentalDesign
+    }
+
+    OfferId getIdentifier() {
+        return OfferId.from(offerId)
+    }
+
+    void setIdentifier(OfferId identifier) {
+        this.offerId = identifier.toString()
+    }
+
+    Affiliation getSelectedCustomerAffiliation() {
+        return selectedCustomerAffiliation
+    }
+
+    void setSelectedCustomerAffiliation(Affiliation selectedCustomerAffiliation) {
+        this.selectedCustomerAffiliation = selectedCustomerAffiliation
+        recomputeWithAffiliation()
+    }
+
+    private void recomputeWithAffiliation() {
+        aggregateCosts()
+    }
+
+    private void updateVatRatio() {
+        this.vatRatio = vatRatio(selectedCustomerAffiliation.country)
+    }
+
+    private void updatePriceBeforeTax() {
+        this.priceBeforeTax = BigDecimal.valueOf(overhead).add(salePrice)
+    }
+
+    private void updateOverheadAmount() {
+        this.dataGenerationOverhead = dataGenerationSalePrice * overheadRatio
+        this.dataAnalysisOverhead = dataAnalysisSalePrice * overheadRatio
+        this.dataManagementOverhead = dataManagementSalePrice * overheadRatio
+        this.externalServiceOverhead = externalServiceSalePrice * overheadRatio
+        this.overhead = dataGenerationOverhead
+                .add(dataAnalysisOverhead)
+                .add(dataManagementOverhead)
+                .add(externalServiceOverhead)
+    }
+
+    double getOverhead() {
+        return BigDecimal.valueOf(overhead).doubleValue()
+    }
+
+    protected void setOverhead(double overhead) {
+        this.overhead = overhead
+    }
+
+    double getOverheadRatio() {
+        return overheadRatio
+    }
+
+    Optional<ProjectIdentifier> getAssociatedProject() {
+        return Optional.ofNullable(associatedProject)
+    }
+
+    void setAssociatedProject(ProjectIdentifier associatedProject) {
+        this.associatedProject = associatedProject
+    }
+
+    List<ProductItem> getItems() {
+        return items.collect()
+    }
+
+    void setItems(List<ProductItem> items) {
+        clearItems()
+        addItems(items)
+    }
+
+    private void clearItems() {
+        items.clear()
+        dataManagementItems.clear()
+        dataAnalysisItems.clear()
+        dataGenerationItems.clear()
+        externalServiceItems.clear()
+    }
+
+    void addItems(List<ProductItem> items) {
+        items.forEach(it -> addItem(it.getProduct(), it.getQuantity(), it.offerPosition()))
+        aggregateCosts()
+    }
+
+    private void aggregateCosts() {
+        //ATTENTION: TEMPORAL COUPLING! Do not change the order
+        updateSalePrices()
+        //-
+        updateOverhead()
+        updatePriceBeforeTax()
+        updateVat()
+        updatePriceAfterTax()
+        //-
+        updateDiscountAmount()
+    }
+
+    private void updateVat() {
+        TaxPolicy taxPolicy = TaxOffice.policyFor(selectedCustomerAffiliation.category, selectedCustomerAffiliation.country)
+        vatRatio = taxPolicy.getVatRatio()
+        taxAmount = taxPolicy.calculateTaxes(priceBeforeTax).setScale(2, RoundingMode.HALF_UP)
+    }
+
+    private void updateOverhead() {
+        updateOverheadRatio()
+        updateOverheadAmount()
+    }
+
+    private void updatePriceAfterTax() {
+        this.priceAfterTax = priceBeforeTax.add(taxAmount)
+    }
+
+    /**
+     * This method does not recompute the prices! For internal use only!
+     * @param product the product for which an item shall be added
+     * @param quantity the amount of the product
+     * @param offerPosition position on the offer
+     */
+    private void addItem(Product product, Double quantity, int offerPosition) {
+        ProductItem productItem = new ProductItem(this, product, quantity)
+        productItem.setOfferPosition(offerPosition)
+        this.addItemToGroup(productItem)
+        this.items.add(productItem)
+    }
+
+    /**
+     * This method is executed after loading the offer from the database.
+     * It is responsible to update all the prices
+     */
+    @PostLoad
+    protected void onPostLoad() {
+        loadFields()
+        items.forEach(ProductItem::refresh)
+        items.forEach(this::addItemToGroup)
+        aggregateCosts()
+        expireNinetyDaysAfterCreation()
+    }
+
+    private void loadFields() {
+        getItems()
+        getAssociatedProject()
+    }
+
+    private void updateSalePrices() {
+        dataGenerationSalePrice = dataGenerationItems.getSalePrice()
+        dataAnalysisSalePrice = dataAnalysisItems.getSalePrice()
+        dataManagementSalePrice = dataManagementItems.getSalePrice()
+        externalServiceSalePrice = externalServiceItems.getSalePrice()
+        salePrice = dataGenerationSalePrice
+                .add(dataAnalysisSalePrice)
+                .add(dataManagementSalePrice)
+                .add(externalServiceSalePrice)
+    }
+
+
+    List<ProductItem> getDataManagementItems() {
+        // Create a copy of the item collection
+        return dataManagementItems.iterator().collect()
+    }
+
+    List<ProductItem> getDataAnalysisItems() {
+        return dataAnalysisItems.iterator().collect()
+    }
+
+    List<ProductItem> getDataGenerationItems() {
+        return dataGenerationItems.iterator().collect()
+    }
+
+    List<ProductItem> getExternalServiceItems() {
+        return externalServiceItems.iterator().collect()
+    }
+
+    static OfferV2 copyOf(OfferV2 original) {
+        return original.copy()
+    }
+
+    private OfferV2 copy() {
+        OfferV2 offerCopy = new OfferV2()
+
+        //sorted alphabetically
+        offerCopy.setAssociatedProject(this.getAssociatedProject()?.orElse(null))
+        offerCopy.setCreationDate(this.getCreationDate())
+        offerCopy.setCustomer(this.getCustomer())
+        offerCopy.setExperimentalDesign(this.getExperimentalDesign())
+        offerCopy.setExpirationDate(this.getExpirationDate())
+        offerCopy.setIdentifier(this.getIdentifier())
+        offerCopy.setProjectManager(this.getProjectManager())
+        offerCopy.setProjectObjective(this.getProjectObjective())
+        offerCopy.setProjectTitle(this.getProjectTitle())
+        offerCopy.setSelectedCustomerAffiliation(this.getSelectedCustomerAffiliation())
+
+        //fields
+        offerCopy.setItems(this.getItems())
+
+        return offerCopy
+    }
+
+    /**
+     * Updates the overhead ratio and any price depending on it
+     * <ul>
+     *   <li>overhead costs</li>
+     *   <li>price before tax</li>
+     *   <li>tax amount</li>
+     *   <li>price after tax</li>
+     * </ul>
+     */
+    private void updateOverheadRatio() {
+        def category = selectedCustomerAffiliation.getCategory()
+        this.overheadRatio = determineOverheadRate(category)
+    }
+
+    private static BigDecimal determineOverheadRate(AffiliationCategory category) {
+        if (category == AffiliationCategory.INTERNAL) {
+            return BigDecimal.ZERO
+        }
+        if (category == AffiliationCategory.EXTERNAL_ACADEMIC) {
+            return new BigDecimal("0.2")
+        }
+        return new BigDecimal("0.4")
+    }
+    //Note this is only used for Reporting and not in the offer
+    private void updateDiscountAmount() {
+        this.discountAmount = dataGenerationItems.discountAmount
+                .add(dataAnalysisItems.discountAmount)
+                .add(dataManagementItems.discountAmount)
+                .add(externalServiceItems.discountAmount)
+    }
+
+    private void expireNinetyDaysAfterCreation() {
+        expirationDate = creationDate.plusDays(90)
+    }
+
+    private static class ItemGroup extends ArrayList<ProductItem> {
+        BigDecimal getSalePrice() {
+            this.stream().map(ProductItem::getSalePrice).reduce(BigDecimal.ZERO, BigDecimal::add)
+        }
+
+        BigDecimal getDiscountAmount() {
+            return this.stream().map(ProductItem::getDiscountAmount).reduce(BigDecimal.ZERO, BigDecimal::add)
+        }
+    }
+
+
+    private static class OptionalStringConverter implements AttributeConverter<Optional<String>, String> {
+
+        @Override
+        String convertToDatabaseColumn(Optional<String> s) {
+            return s.orElse("")
         }
-        def space = new ProjectSpace(splittedIdentifier[1])
-        def code = new ProjectCode(splittedIdentifier[2])
-        identifier = new ProjectIdentifier(space, code)
-      } catch (Exception ignored) {
-        throw new IllegalArgumentException(String.format("Cannot parse %s to a project identifier.", projectIdentifier))
-      }
-      return identifier
-    }
-  }
+
+        @Override
+        Optional<String> convertToEntityAttribute(String s) {
+            // If the String is null or empty, we return an empty Optional
+            return s ? Optional.of(s) : Optional.empty() as Optional<String>
+        }
+    }
+
+    private static class OptionalProjectIdentifierConverter implements AttributeConverter<ProjectIdentifier, String> {
+
+        @Override
+        String convertToDatabaseColumn(ProjectIdentifier projectIdentifier) {
+            if (projectIdentifier) {
+                return projectIdentifier.toString()
+            } else {
+                return null
+            }
+        }
+
+        @Override
+        ProjectIdentifier convertToEntityAttribute(String projectIdentifier) {
+            ProjectIdentifier identifier = null
+            if (!projectIdentifier) {
+                return identifier
+            }
+            try {
+                /*
+                A full openBIS project ID has the format: '/<space>/<project>', where
+                <space> and <project> are placeholders for real space and project names.
+                 */
+                def splittedIdentifier = projectIdentifier.split("/")
+                if (splittedIdentifier.length != 3) {
+                    throw new RuntimeException(
+                            "Project identifier has an unexpected number of separators: ${projectIdentifier}. " +
+                                    "The expected format must follow this schema: \'/<space>/<project>\'")
+                }
+                def space = new ProjectSpace(splittedIdentifier[1])
+                def code = new ProjectCode(splittedIdentifier[2])
+                identifier = new ProjectIdentifier(space, code)
+            } catch (Exception ignored) {
+                throw new IllegalArgumentException(String.format("Cannot parse %s to a project identifier.", projectIdentifier))
+            }
+            return identifier
+        }
+    }
 }
diff --git a/offer-manager-domain/src/main/groovy/life/qbic/business/products/ProductItem.java b/offer-manager-domain/src/main/groovy/life/qbic/business/products/ProductItem.java
index 9afe8b242..fa37d0b20 100644
--- a/offer-manager-domain/src/main/groovy/life/qbic/business/products/ProductItem.java
+++ b/offer-manager-domain/src/main/groovy/life/qbic/business/products/ProductItem.java
@@ -15,6 +15,7 @@
 import javax.persistence.Id;
 import javax.persistence.JoinColumn;
 import javax.persistence.ManyToOne;
+import javax.persistence.PostLoad;
 import javax.persistence.Table;
 import javax.persistence.Transient;
 import javax.persistence.UniqueConstraint;
@@ -42,9 +43,33 @@ public class ProductItem {
   @JoinColumn(name = "productId", nullable = false)
   private Product product;
 
+  @Column(name = "category")
+  private String productCategory;
+
   @Column(name = "quantity", nullable = false)
   private Double quantity;
 
+  @Column(name = "description", length = 2500)
+  private String description;
+
+  @Column(name = "productName", length = 500)
+  private String productName;
+
+  @Column(name = "internalUnitPrice", nullable = false)
+  private Double internalUnitPrice;
+
+  @Column(name = "externalUnitPrice", nullable = false)
+  private Double externalUnitPrice;
+
+  @Column(name = "unit")
+  private String unit;
+
+  @Column(name = "productReference")
+  private String productReference;
+
+  @Column(name = "serviceProvider", nullable = false)
+  private String serviceProvider;
+
   @ManyToOne(optional = false)
   @JoinColumn(name = "offerId", nullable = false)
   private OfferV2 offer;
@@ -55,13 +80,84 @@ public class ProductItem {
   @Transient
   private BigDecimal discountRate;
 
+  /**
+   * Stores the latest position on the offer.
+   * <p>
+   * A negative value indicates no specific position was stored in the item.
+   */
+  @Column(name = "offerPosition")
+  private int offerPosition = -1;
+
   public ProductItem(OfferV2 offer, Product product, Double quantity) {
     this.offer = requireNonNull(offer, "Offer must not be null");
     this.product = requireNonNull(product, "Product must not be null");
     this.quantity = requireNonNull(quantity, "Quantity must not be null");
+    // Ensure immutability of product information (including prices!)
+    readProductValues(product);
+    this.product = product;
     refreshProductItem();
   }
 
+  /**
+   * Reads all product values and saves them in the {@link ProductItem} class.
+   * <p>
+   * This ensures immutability for prices and other product related properties and conserves the
+   * product state at the time-point of addition to the offer.
+   *
+   * @param product the product to read
+   * @since 1.6.0
+   */
+  private void readProductValues(Product product) {
+    this.productCategory = product.getCategory();
+    this.description = product.getDescription();
+    this.productName = product.getProductName();
+    this.internalUnitPrice = product.getInternalUnitPrice();
+    this.externalUnitPrice = product.getExternalUnitPrice();
+    this.unit = product.getUnit();
+    this.productReference = product.getProductId();
+    this.serviceProvider = product.getServiceProvider();
+  }
+
+  /**
+   * Helper method for the transition to make product values immutable, once they have been added to
+   * an offer.
+   * <p>
+   * The copy of values will only happen once, if the product reference field is null, which means
+   * the copy has not been done yet.
+   *
+   * @since 1.6.0
+   */
+  @PostLoad
+  private void triggerProductCopy() {
+    if (Objects.isNull(this.productReference)) {
+      readProductValues(product);
+    }
+  }
+
+  /**
+   * Sets the position information on the offer the item should be placed
+   * <p>
+   * A negative value indicates no positional information.
+   *
+   * @param position a positive value >= 0 indicating a position on the offer
+   * @since 1.6.0
+   */
+  public void setOfferPosition(int position) {
+    this.offerPosition = position;
+  }
+
+  /**
+   * The position on the offer >= 0.
+   * <p>
+   * Is negative, if no positional information is available.
+   *
+   * @return
+   * @since 1.6.0
+   */
+  public int offerPosition() {
+    return offerPosition;
+  }
+
   protected ProductItem() {
     //needed for hibernate
   }
@@ -89,7 +185,7 @@ protected void refresh() {
   private void refreshProductItem() {
     validateObjectState();
     AffiliationCategory affiliationCategory = offer.getSelectedCustomerAffiliation().getCategory();
-    unitPrice = determineUnitPrice(affiliationCategory, product);
+    unitPrice = determineUnitPrice(affiliationCategory);
     discountRate = getDiscountRate(affiliationCategory, BigDecimal.valueOf(quantity),
         product.getCategory());
   }
@@ -111,10 +207,18 @@ private BigDecimal getDiscountRate(AffiliationCategory affiliationCategory, BigD
     BigDecimal quantityDiscountRate =
         calculateQuantityDiscountRate(quantity, productCategory);
     BigDecimal storageDiscountRate =
-        calculateDataStorageDiscountRate(affiliationCategory, productCategory);
+        calculateDataStorageDiscountRate(affiliationCategory);
     return quantityDiscountRate.max(storageDiscountRate);
   }
 
+  protected Double getInternalUnitPrice() {
+    return this.internalUnitPrice;
+  }
+
+  protected Double getExternalUnitPrice() {
+    return this.externalUnitPrice;
+  }
+
   /**
    * <p>The relevant unit price for a product in an offer depends on the customer's affiliation.
    * The current business policy is to provide base prices for internal and external customer
@@ -122,16 +226,14 @@ private BigDecimal getDiscountRate(AffiliationCategory affiliationCategory, BigD
    * base price.</p>
    *
    * @param affiliationCategory internal, external or external academic
-   * @param product             the product of interest
    * @return the determined base price
    */
-  protected static BigDecimal determineUnitPrice(AffiliationCategory affiliationCategory,
-      Product product) {
+  private BigDecimal determineUnitPrice(AffiliationCategory affiliationCategory) {
     if (affiliationCategory == AffiliationCategory.INTERNAL) {
-      return BigDecimal.valueOf(product.getInternalUnitPrice()).setScale(2,
+      return BigDecimal.valueOf(this.internalUnitPrice).setScale(2,
           RoundingMode.HALF_UP);
     }
-    return BigDecimal.valueOf(product.getExternalUnitPrice())
+    return BigDecimal.valueOf(this.externalUnitPrice)
         .setScale(2, RoundingMode.HALF_UP);
   }
 
@@ -141,9 +243,13 @@ protected static BigDecimal determineUnitPrice(AffiliationCategory affiliationCa
    * on data storage products.
    *
    * @param affiliationCategory the considered affiliation category for discount determination
-   * @param productCategory     the considered product category for discount determination
    * @return the discount rate for the provided product. In range [0,1]
    */
+  private BigDecimal calculateDataStorageDiscountRate(
+      AffiliationCategory affiliationCategory) {
+    return calculateDataStorageDiscountRate(affiliationCategory, this.productCategory);
+  }
+
   protected static BigDecimal calculateDataStorageDiscountRate(
       AffiliationCategory affiliationCategory, String productCategory) {
     if (productCategory.equalsIgnoreCase("data storage")
@@ -262,4 +368,5 @@ public boolean equals(Object o) {
   public int hashCode() {
     return Objects.hash(product, quantity, offer);
   }
+
 }
diff --git a/offer-manager-domain/src/main/groovy/life/qbic/business/projects/create/CreateProjectDataSource.groovy b/offer-manager-domain/src/main/groovy/life/qbic/business/projects/create/CreateProjectDataSource.groovy
index aa1b82121..2b8e1bc35 100644
--- a/offer-manager-domain/src/main/groovy/life/qbic/business/projects/create/CreateProjectDataSource.groovy
+++ b/offer-manager-domain/src/main/groovy/life/qbic/business/projects/create/CreateProjectDataSource.groovy
@@ -1,9 +1,8 @@
 package life.qbic.business.projects.create
 
-
 import life.qbic.business.exceptions.DatabaseQueryException
-import life.qbic.datamodel.dtos.projectmanagement.Project
 import life.qbic.datamodel.dtos.business.ProjectApplication
+import life.qbic.datamodel.dtos.projectmanagement.Project
 
 /**
  * <h1>Access to the project management datasource</h1>
diff --git a/offer-manager-domain/src/test/groovy/life/qbic/business/offers/policies/taxes/TaxOfficeSpec.groovy b/offer-manager-domain/src/test/groovy/life/qbic/business/offers/policies/taxes/TaxOfficeSpec.groovy
index a76475072..a72d4db7c 100644
--- a/offer-manager-domain/src/test/groovy/life/qbic/business/offers/policies/taxes/TaxOfficeSpec.groovy
+++ b/offer-manager-domain/src/test/groovy/life/qbic/business/offers/policies/taxes/TaxOfficeSpec.groovy
@@ -1,7 +1,7 @@
 package life.qbic.business.offers.policies.taxes
 
-import life.qbic.business.persons.affiliation.AffiliationCategory;
-import spock.lang.Specification;
+import life.qbic.business.persons.affiliation.AffiliationCategory
+import spock.lang.Specification
 
 class TaxOfficeSpec extends Specification {
 
diff --git a/offer-manager-domain/src/test/groovy/life/qbic/business/persons/search/SearchPersonSpec.groovy b/offer-manager-domain/src/test/groovy/life/qbic/business/persons/search/SearchPersonSpec.groovy
index 1798c1445..b0baeebc9 100644
--- a/offer-manager-domain/src/test/groovy/life/qbic/business/persons/search/SearchPersonSpec.groovy
+++ b/offer-manager-domain/src/test/groovy/life/qbic/business/persons/search/SearchPersonSpec.groovy
@@ -1,9 +1,6 @@
 package life.qbic.business.persons.search
 
 import life.qbic.business.exceptions.DatabaseQueryException
-import life.qbic.business.persons.search.SearchPerson
-import life.qbic.business.persons.search.SearchPersonDataSource
-import life.qbic.business.persons.search.SearchPersonOutput
 import life.qbic.datamodel.dtos.business.Customer
 import spock.lang.Specification
 
diff --git a/pom.xml b/pom.xml
index bccfe5918..1539faec6 100644
--- a/pom.xml
+++ b/pom.xml
@@ -127,7 +127,7 @@
 			<dependency>
 				<groupId>life.qbic</groupId>
 				<artifactId>data-model-lib</artifactId>
-				<version>2.20.0</version>
+				<version>2.22.0</version>
 			</dependency>
 			<dependency>
 				<groupId>com.vaadin</groupId>