Trainer or rollers. You can get a nice trainer used off Craig's list for not much... I paid $125 for a very nicely unused Kurt Kinetic. You shoulnd't have to take the rear wheel off, and most kinds collapse down to put away when you aren't using tem.

As for stationary bike.... I visualize the kind grandma had in the basement and that's....ick. I wouldn't' consider anything less that a spin-type bike if I was going to get one.