Have them demonstrate that ALL appliances work in ALL modes. No matter the temperature, run the a/c, furnace, water heater on elec/propane, refrig on elec/propane, stove, oven, microwave. Have the fresh water system pressurized the whole time, look for leaks underneath. Run the slideouts, power jacks if equipped.
Yeah it's all under warranty but it's a royal pain to have to return it for repairs, especially when you have a trip planned. Years ago, the furnace in our brand new trailer would not fire up. Fortunately I checked it in time for the dealer to repair prior to a long trip.
