I don't want to rain on your parade.... but unless you are very mechanically skilled, you will be better off selling it for scrap. There is no gasket, caulk, or piece of rubber on that thing that is not completely dry rotted and cracked. It may also have a good bit of mouse damage.
It may not be molded/rotted if it's spent most of its life in Arizona.
Now if you have some remote place you could park it and use it for a cabin, it might function like a hard-sided tent. Get it there on a flat-bed tow truck. Put it up on blocks. You could replace all the soft furnishings---mattress, sofa, etc, and use it for a camping spot.
