I have a black futon with black mattress for sale. It's in very good condition and is surprisingly comfortable, even for somebody who's over 6'2". It does help to put additional padding underneath the bedsheet, though.
It conveniently fits in my tiny apartment, so it's great for both apartments or dorm rooms. And there's enough space underneath to store a fair amount of stuff.
I'm asking 200$. If you'd like to come and check it out, please let me know. It would need to be picked up as close to May 12th as possible (since I'd like something to sleep on until I leave...). You can contact me at email@example.com or call/text 717.779.7522.