After all Actors, Goals, Use Cases, User Stories, and Requirements have been documented, we need to explore what data is associated with each workflow. This includes documenting all data information (generic / custom user-defined fields and API Information) for all systems. (CRM, ERP, Third Part Applications/Plugins, Payment Processors)
Identify all Existing Data Fields, User Defined Fields, and Data Workflows/ Internal Business Processes that are associated with each workflow. Once all have been identified and documented, it is time to analyze the data in order to determine the best possible development implementation for each client deliverable.

Example: Simple Web Sequence Diagram showing the Order Data Workflow between Epicor and Salesforce
All Generic and Custom User Defined Fields that are identified as part of a Use Case Workflow need to mapped to their respective fields in whichever system the data is being pulled from/pushed to.

Example: Sage 300 Item Field Mappings for an eCommerce Application\

Example: Sage 300 Customer Field Mappings for an eCommerce Application

Example: Sage 300 Order Field Mappings for an eCommerce Application