What to Add: Garage Apartment, Detached In-law Suite, Other?

[Derek Houck]

I am currently renting my aunt’s old house for her as a single family rental in AA county Maryland. She’s now in assisted living and won’t be moving back. I wanted to split the appx. 1/2 acre lot but after talking to the county it may not be possible because it’s septic. Running sewer may be too much $$- it’s 4 houses away.

There’s a nice attached double garage with really high ceilings. There’s also plenty of room to build a stand alone apartment.

First, how do I find out what’s legal and if it’s possible to rent these other proposed units? I guess I also need separate meters/boxes. Addresses, too, that just occurred to me. And, of course, what makes the most financial sense. 

I appreciate any ideas, especially first steps.

Thanks