Jesus that pisses me off. You're living your life minding your own business and you have to deal with that BS. You should install a camera at the very top of your garage pointing to the street, and one inside the garage. Very easy installs with a dvr. You can also hook it up to your Internet and view them anywhere you are. I have that at home. I like the chaining of the garage door idea, and the razor blades. Mine is outside and I don't care who watches it. They'd have to know how to put the cherry picker together, get the engine back in and wire everything up.
Sorry I meant to say chain the car to the anchors. I also have a hole in my garage door track that I put a bolt through so the door can't be opened. The wheels in the track hits the bolt and won't go up any farther.