Keep the 240D - probably one of the most reliable cars MB ever
made. I wouldn't let a punk be the cause of me giving up such
a fine car.
One way or the other, record their license plate number.
Lots of power on the WEB. For a few bucks you can find out who owns the car and where they live.
Now you're free to drop by the kids house with your adjustable crescent wrench anytime you like.
Question is - do you want to risk everything you've put together(family, home, job, etc.) over a mindless teenager?