I have a 7.2 or 7.4 can't remember, but it holds 4 cornies so I'd think a carboy could fit no problem. You could probably even build a shelf over the hump, add a collar and be able to put a carboy and some cornies in there.
Easily with room left over for a few cornies. I looked at one two days ago and almost bought the thing. Then I saw the 9cf one next to it and almost bought that one LOL. Gonna save the funds for Craigslist though and see if I can't take advantage of someone else's misofrtune/goodwill.
That is a good point. A standard dorm fridge will hold a 5 gallon fermenter. If you are looking to buy just for this reason I would say go smaller/cheaper or look into how many fermenters you can fit into the chest freezers. Also, a glass carboy on the floor a chest freezer might be tough to lift out (some people use milk crates). Just things to think about.