So I haven't really thought about this, but now that I am, I'm thinking that Beast Boy should have a roommate.

I'm thinking some dingy little apartment on the edge of town near the Wall, since that's where he works. Also since BB is an enormous slob, it would be ideal for his roommate to be a neatfreak. Imagine a line drawn down the middle of the living room with Beast Boy's side being filled with piles of comic books, drifts of dirty clothes, and the other side being sparkling clean and neat.