I've got plenty of room at my house - send 'em on over
Personally, I would keep them at room temp, and as Isamu stated, out of the sunlight. If you got a sizeable collection, you're talking about thousands of dollars of plastic that will be worth little to mothing if the plastic deteriorates from UV or temperature induced embrittlement.
Just stuff them under your bed, the back of the linen closet, behind the couch, etc.