Office space in an RV wheel under the bed. Could also build a fold/lift up perm wooden station so items don't have to be put up & down when you put the bed down. Maybe even on of those lift up coffee tables?
You can pack a whole lot of fun into this Momentum Fifth Wheel Toy Hauler by Grand Design! There is so much sleeping space for a few extra buddies to tag along, one and a half baths, a fireplace (Camping Hacks Sleeping)