Not all of us are lucky enough to have a designated guest room, but the best rollaway beds make it possible even in small spaces. ... twin-size rollaway bed to set you back about $150 to $300.

Queen-size beds, at 60 inches wide and 80 inches long, are 21 inches wider and 5 inches longer than a twin bed and 6 inches wider and 5 inches longer than a double bed.