In addition to what Handbasket said, make sure everything works! Stove, refr, microwave, water heater, furnace / thermostat, antenna deployment mechanism, fantastic fan, smoke detector, water pump, electric couch, if so equiped, and generator running air conditioner and or microwave.
Also, check the air bag suspension mechanisms... either the remote fill, or the manual fill air valves under the rear bumper.
Enjoy the adventure!