Small Servicer Definition

My bank has never gotten close to servicing the 5,000 mortgage loans required to be a "large servicer." We have always been a small servicer. However, we have acquired a new institution and this will be our first year to be over that threshold. I want to be sure I understand the definition of "mortgage" for RESPA. A Federally Related Mortgage includes owner and non-owner occupied properties; however, it excludes temporary financing and mortgages done on a commercial loan. Do I have this straight? Is there anything I am missing?