L.S.
I know someone who made one and put wheels on the bottom so it slid under their little ones bed. Maybe you can find a used one (not as pricey) and cut the legs off so it can fit under a bed or couch while not in use. We live in a 3 bedroom house and my son got a plastic one from his grandparents. The legs are not removable and it takes up his whole room! Although we love it, we really wish we could down size it!