Seems like a waste to run a 5 horse gas motor to just run the water pump. With just a little more power you could run a vacuum off the same motor and have a real truckmount. Gas for the motor, Diesel for the burner, gas for the vehicle and three different electrical outlets for the rotovac and the vacuum. Setup and tear down with a waterline to the van for cold water, hot waterline to the house, three separate 120 v circuits seems like about the same as just using a regular porty.