There's lots of info in the forum on what to look for during a Pre-Delivery Inspection (PDI). There should be water in the fresh water tank and a full bottle of propane so you can operate all faucets, flush the toilet, make sure the water heater and furnace work, etc. The refrigerator takes awhile to cool down so hopefully they either plugged it in or put it in gas mode. Open all cabinet doors and storage doors checking for loose or missing hardware. Check all lights and switches. If this is your first camper it's best to have two people listening to what the dealer is saying and take notes.
I did an axle flip on a pop-up to increase ground clearance. But as a result it also caused the stabilizer jacks to max out where I had to carry blocks to place under them. So far I haven't had a problem with clearance even on dirt roads. But obviously you could drag the bottom - as with any trailer.
Looking at my 17FQ I'm more concerned with damage to the drain point if something was kicked up from the tire. I'm considering adding a plate (or even a heavy mud flap) just behind the tires.
Barry, MSgt, USAF, Ret. & Rose
2015 Nissan Frontier V6
2014 Coachmen Viking 17FQ