You'll need to test every component too. Every outlet, interior and exterior lighting, fridge on 12v, gas and 120V. Run the water with a hose connected to city water and from the 12v pump. Fill all the holding tanks. Run all the faucets. How old are the propane tanks? Yes, they age out too. 12 years now, then they have to be recertified. Is battery(ies) old? Is the caulking on the roof dried up and cracked? Is the roofing material chalky? Man, this list is endless. Take a seasoned RV friend with you. He may notice something you don't because of your excitement level. Then you gotta be sure your truck can handle the weight of the RV. But, I think the absolute most important thing is making sure that it is the model YOUR WIFE wants.
