One of my buddies has a van that he uses for doing deliveries like in shipping wars or whatever that show is. I think he has an E350. He has the inside set up with a bed on hinges that can be folded up flat against the wall. He also ran a small house AC out the back window that he powers with a small Honda generator. The generator us mounted on the hitch receiver with rubber mounts for vibration. When he is driving, he puts the generator on the passenger floorboard, folds up his bed against the wall, and still has all of the cargo area.