Welcome to the forum Bill, and congrats on the new rig.
A camera is a good idea it will pull back and awful lot of things that are impossible to remember.
Here is a link for a PDI if you are interested. I would recommend down loading a copy to take along and one to send to your dealer to let them know what you expect.
Welcome and congrats. The video camera was very helpful to us when we recorded our pdi. Just remember if it opens, closes, turns on or off or even moves you want it demonstrated and you return the demo. Don't just let them tell you how it works. Learn every switch etc. Check everywhere for signs of leaks etc. Have them open up and show you the water heater and water pump (I have no idea where these are on a MH). Have them walk you through the winterizing and dewinterizing processes. Good luck and may it bring you many happy trips.