Hello, I am hopefully a soon-to-be Porsche owner and am considering a 2007 911 Carrera S (sold by a private seller in the Los Angeles area). I have done as much due diligence as I know of: CARFAX; NMVTIS report; have seen and driven the car; have verified the title; and am planning on having a PPI accomplished by Woodland Hills Porsche. Does anyone have any other advice to try to make sure that I am buying a quality vehicle? Many thanks.