Firstly make sure they have 12v battery, 110v power and water line propane hooked in.
Try all the appliances, lights, tv, radio, microwave outside light etc.that uses power. Make sure they all work and also that no breakers or fuses blow on 110v and just 12v battery powered. Turn on hot water from cold and you should be able to hear the element kick in on startup.
Run stove top, light oven, start fridge, furnace and hot water and make sure all start on propane. Fridge and furnace can be seen or easily heard by ear running from outside vents.
Check all cupboard doors for straightness and give a light pull to make sure they don't pop off. I have heard many with a door in hand. Pull all drawers out and confirm they slide in and out properly.Open and close any interior doors to confirm they all work smooth and don't need any adjustments. Check for chip s and dings in wood, counter tops, plastic mouldings etc.
Turn on water at all faucets, shower head, outside shower and make sure they all work and check underneath the sinks with water running that all the drains connections are tight and not leaking.(common issue)Flush toilet and confirm it is flushing properly and no leaks. Learn how to winterize the unit if in a colder climate and needs to be done.
Lift the bed if it has a lift and confirm it is smooth and check couch if it is movable and dining area chairs or bench to be sure all pieces lift or move as they should.
Open and close all vents to confirm they work correctly and look for any water stains in case they were not sealed correctly.
Open and close all windows and doors to confirm they are moving freely and check for any open areas around doors.
Check tires, air pressures, run stabilizers up and down, pull awning in and out yourself, run tongue jack up and down. Check siding for flaws or possible dings etc.
Try draining some of the water you ran in earlier tests to confirm you know the drain system and the gates are working properly. Have them hook into the black tank cleaner to confirm it is working with no leaks.
Climb up on ladder to confirm roof all looks smooth and have tech show you how to do caulk maintenance as it if very important to know and do every year.
Crawl underneath the unit and check the undercover and look for any abnormalities.
Check brakes, hitch for proper alignment.
Take lots of notes and pics if you need to. If I missed anything which I probably did refer to all the above posts. My last unit took us about 3 hours before we were done and we did find several small things. They had the tech fix them all before we left and we have never returned.
The good thing there was no major issues after that I couldn't fix in a minute and I was smarter than going in and do all my own maintenance with tips from the tech guy by asking a lot of questions.
