Object mapping - Sometimes, objects don't map 1:1, and on one system, one object can be represented in two objects on the other system. This has implications on the integration flow
Field mappings - Please request our Google sheet template as an ideal basis
Custom fields - If one system allows custom fields, how are they handled in the other system? Can they be added by users easily, and how should the integration handle unexpected new custom fields?
Data model relations - through what unique / foreign keys are objects connected?
Validation - Do the systems provide validation of data (length, some characters only, ...), and how are they enforced? If they are not enforced, there are several ways, e.g., the Validation Helper and the replace('#', '')Jinja-function to do this on our side.
Pagination - For large data sets, how is pagination taken care off to loop over lists?
Filtering - Can views, lists, or collections be filtered via the API?
Sorting - Can views, lists, or collections be sorted via the API?
Transformation of data,...
e.g., one system uses UTC-timestamps, the other German timestamps; how is the transformation done?
One system uses EUR and USD as currencies, the other currency symbols $ € - how is the mapping done?
Select drop-down fields: Where are the options stored? What if a new option is generated (e.g., it is easy to generate new options in Salesforce)? Should a default value be used or an error be thrown?