I always wondered if that applied to apartment complexes. Had a killer on the run near the one where I live once, APB, etc. I carried until they caught him, out of simple common sense. But I wondered about the legality of it at the time.
I think a prosecutor would have a hard time nailing you if you defended yourself in your complex.
My complex is very small by Atlanta standards. Perfectly reasonable to walk the .3 acre grounds, packed.