When cars stored inside a locked fence outside the school shop I ran started getting ransacked/vandalized, the ones doing it found out this old man has a few sneaky tricks up his sleeve. There's nothing like opening a car door and getting a faceful of ground cayenne pepper! A piece of PVC pipe duct taped to the steering wheel, a piece of broomstick, a bungee cord, and a cotter pin attached to a string and the inside door handle makes an excellent booby trap. A length of 3/4" PVC 2 feet long will hold four BIG cans of pepper!
Jerry