Baltimore City landlord/tenant questions - NEW PURCHASE

Hello, I am about to close on a 2 unit property in Baltimore City. I currently have the units occupied by tenants from the previous owner. Since I purchased via FHA, I will be occupying one of the units within 60 days while renting out the other unit. What are some things I need to do as an owner for the tenant that is still living in the home? I read up some things and one of them would be to register the home since it was built in the early 1900s and has lead-based paint.

Also, the rental unit has 3 bedrooms which are all rented out to different individuals. Does that mean I need to perform 3 separate lead inspections or can I just go with 1 since it is just 1 unit?