Stuff like this boils my pi$$.
Here's a bloke that's worked hard to buy a nice car, or even if its a company car he still works for it, and some effing rrrrshole thinks it's OK to run into it and drive off, or funny to pour paint on it. People like that really do need a good hiding.
You have my sympathy, OP.
It's all about attitude. I was sitting in my car (early for an interview) in a car park a few weeks ago and this 4x4 pulls up next to me. Someone gets out and bangs the door into mine. They had at seen me.. I roll down the window "Excuse me, would you mind not clouting my car please"
"Oooh sorry" was the very sarcastically blunt reply as they wandered off. They didn't give a shit. Now, there was no damage done but that's really not the point. I did feel like leaving a nice toe sized dent in their door to be honest.