I am working on a home with something I haven’t seen before and you could use some feedback. The home is a large waterfront property. It has an ADU attached to the garage. There is a second entrance to the home ( at the front of the house) inside is a second foyer, then a staircase. The staircase goes upstairs to an apartment with yet another kitchen. How do I address this second apartment in a clearly single family home. it is going FHA reverse. Than you for your feedback.