Unfortunately, there are a lot of scumbags in this world who fail to realize that a person's car is often of huge importance to their livelihood. How am I supposed to drive to work if some local punk has decided to smash my windscreen or let the air out of my tires? How am I supposed to sleep at night if I'm constantly worrying about somebody damaging my vehicle? It doesn't really matter whether the vandal is somebody with a personal grudge against me or some random drunk passerby. What does matter to me is that the culprit is thwarted or caught. If I catch them after-the-fact, I can press criminal charges and look for reparations (including compensation for any loss-of-earnings that may have occurred while I was unable to attend work). Basically, if I catch them after-the-fact, I can do my best to make sure that they regret the moment they decided to lay hands on my car.
Fortunately, there are a few ways to combat this sort of thing. There are also a lot of gadgets that may help you deter or catch car vandals in the act.
The first one is a no-brainer. If you have a garage or an enclosed parking space that isn't easily accessible to the outside public, then use it.
Good lighting is a must! Try to avoid parking in dark areas. If you park your car in front of your house, think about investing in a motion light, which will turn on whenever somebody is close enough to trigger the sensor. This may frighten off a would-be attacker. Nobody likes being "visible" when they're doing something illegal.
Run on from the previous point. Try to park your car as close to your home as possible! This way, you can keep an eye on your car and maybe even put up some surveillance equipment.
Fake Surveillance Camera
If you're not willing to invest in a real surveillance camera, you could setup a dummy camera, which will act as a deterrent. If somebody sees what looks to be a camera, its doubtful that they'll damage your car in plain sight of it.
Real Surveillance Camera
If you're wanting to deter AND catch vandals after-the-fact, then a night vision camera is probably your best choice. You could also get a battery-powered Wifi camera and put it inside your car if you're willing to experiment a bit. Just make sure that the footage is being recorded somewhere safe inside your house (hence the choice of a WiFi cam). You don't want a thief doing a smash and grab on your footage.
If you've recently fallen victim to an attack on your car, talk to your neighbors and let them know about the incident. If they own a vehicle themselves, they will probably share in your worry and keep an eye out for suspicious persons. If the culprit happens to be a neighbor, you talking about the incident might put some heat on them and in turn, make them worry about whether you're onto them or not.
Do not retaliate
Tit-for-tat vandalism will end in tears. Nobody will win in the end and none of you will be able to take the moral high ground in court.