I know PPG makes a graffiti resistant paint that they use on New York city subway cars. I have a friend who is the local PPG rep. I could check with him as to what it is. I have become a friend of urethane truck bed liner coating. I did paint the underside of my car but after i finished i realized that i just don't want a trophy piece that I have to keep super clean. When sprayed with a schutz gun it looks like factory undercoating and is tough as nails. hit it with a hose and its all clean again. Plus its a sound deadener.