I got a customer who wants a service to supply a motor home and his utility building. The utility building is 12x16. Right now there is no outlets or light in the utiltiy bldg. He also wants to have an outlet he can plug his motor home into. My thought is to mount a 100 amp service on the utilty bldg. with outlets with in use covers for his motor home. Install at least one light and one outlet in the utility bldg. with the outlet on a GFCI. Is there anything in code that limits the size of the bldg. that a service is to be mounted too? I myself cannot think of any now. The bldg. is permanent but of course the motor home is not. The motor home has a 120 volt cord on it. Anything wrong with my idea here. I've never had to install a service on a bulding this small, but I don't think there is any violations just so it is at least 100 amps.