There's a PDI sheet posted here somewhere. Basically just make sure everything works before you leave. Test water systems. both city and pump, heat, A/C, water heater, lights, etc. Look all over the outside and open every storage door. Operate the slides more than once. Open and close every cabinet door several times. Hook to your TV and make sure the brakes and lights all work. Make sure your dealer tests the charging line too. Make him show you how to a pull test if you're not familiar with that. Make them show you how to make sure the hitch is properly latched. Test the emergency break-away system.