We did this for our last trip. It was just the four of us (me, DH, DD age 7 and DS age 4). DH and I absolutely cannot sleep together on one of those tiny little double beds. So, we each took a bed and we brought two single air mattresses. They both fit in the room just fine. You have to do a little creative maneuvering with the furniture, i.e. move the table and chairs on the other side of the TV cabinet near the sink side of the room. We put the mattress down in an L-shape...one under the window and one like at the foot of the bed. Worked out wonderfully. In the morning before leaving, we just stood them up on their ends against the wall so Mousekeeping would have room to do their thing.