I only have one bike in my room.
I tend to swap between the trials bike one week and the dh bike the next week. I go home every weekend to work as its only a 2 hour train journey so i can swap between bikes easily.
The first 2 years no one ever moaned about my bikes in my room I had 4 in there in the first year when my brother stayed round.
Im at Royal Holloway, its crap for riding but easy to get to the good spots like Reading, London, Esher, Porc etc...