ETL and Informatica

Hi guys,
I need to analyse a project where the source system has two types of sources SAP and non SAP all the SAP data is loaded to SQL server using Informatica from this server it is loaded into other SQL server where the non SAP data is present. and non SAP is stored to SQL using some stored procedures and SSIS packages. Please suggest what questions I can ask them. All the stuff related to these two