Buying a used motorhome

Have the seller run the fridge overnight and have it cold when you get there with or without a paid inspector. Try the fridge on both propane and electric and "automatic" power modes. A fridge replacement costs over $1000. Run the RV generator, let it warm up, then turn on the roof AC, make sure it is cooling then heat a cup of water in the microwave oven. RV Generator should operate roof AC and microwave at the same time. Run the engine and make sure that the dash AC is cooling. Run the furnace and make sure it is heating. Run the fresh water to make sure the electric pump is working. Make sure that the converter/charger is working and charging the house batteries when rig is plugged into shore power or when RV generator is running. Have inspector test charging with voltmeter. Set up awning and look for any damage or holes in awning fabric. Test drive rig as best you can listening for strange noises, and watch for handling problems or brake problems. Check date codes on all tires don't take seller's word for age of tires. Look for sidewall cracks on tires.
Get a list of items that need repair or replacement with estimate for parts and labor.