Sorry about your experience DJ.
I'll probably jinx myself with this comment, but my Boxster has never been vandalized. I've parked in the street in Manhattan when I go out on weekends, I park it in shopping centers in NJ and Long Island all the time, and never a key, spit, spilled drink on it, or any dents. My Litronics have never been stolen either. Knock on wood. I'm thinking that part of the reason for this is that my car is silver color. Maybe would be vandals figure since the car is basically colorless already, why bother keying it?...underneath the paint is basically the same color anyway. LOL
I have, however, had my previous cars keyed- a black BMW 3 series, and a red 944. My Benz CLK coupe, also silver, was never vandalized in any way. Maybe a flashy color that makes vandals think a fresh deep key mark would make a noticeable difference is the culprit?