Any old race fans in the northeast remember the Cassidy Brothers? They hauled their funny car around in an old school bus.
The best one I ever saw was a 65 Dodge 44 passenger school bus converted to haul a stock eliminator car. Lowered, had a Cummins with a six speed, a two speed rear axle, the rear section was cut off and raised and lowered with hydraulics, air, cruise, sleeping area, tunes, this thing was so nice they even kicked around giving "best engineered" at a NHRA event.
For a cheap party barge or tailgater, they're hard to beat.