a question about square footage of a property

[Pete Nater]

Hi, I have a question about square footage of a property.

I'll use a potential deal I'd like to get under contract as an example for me questions. It's 1600 sq ft, 2 story SFR which also has an unfinished basement and unfinished attic. The basement is large enough to finish/convert into a small (maybe 1 bedroom) apt and has a separate entrance, though through the back of the house. The attic is big enough to convert into 2 mid sized rooms and possibly even with a 1/2 bath.

So, If I were to rehab the basement & attic, can I add the extra sq ft to the listing when I go to sell it?

If I convert basement into separate apt, with permits as required of course, does it matter that the entrance is at the back of the property and one would have to walk through an alley, about 4 ft wide, to get to the back?

Thanks