Finding a new place to park would definitely be my first choice. I would think putting a cover on the Motorhome would also protect it from theft. Too much trouble for a thief to have to take it off. Plus, it will protect the rig from the elements while he is gone.
The problem I see with immobilizing the vehicle is that it doesn't keep them out. Unless they can see from the outside that it isn't worth the trouble (like removing one or more tires), they may still get in. If they take the trouble to get into it and find that it can't be moved, they may get pissed and do damage to it.
-Michael
