While going through the pre delivery inspection, make sure you try out every system multiple times with the dealer present. The slides, water pump, heater, air conditioner, all electrical lights... You also need to check the drawers and doors for proper alignment. Check all of the exterior compartments/doors and all electrical outlets. Take an outlet tester with you to be sure things are wired correctly. If you find anything wrong, have it noted and repaired. You may have to have them schedule a repair date but document everything. It is a big investment and you need to take your time.
Good Luck
Paul
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