I added an appearances section to the Mafia III vehicle pages, feel free to add anything you think of. To be clear, I think it's best if the vehicles are driven in missions or cutscenes, by that I mean driven by a named character, not just something driving by. Also, used as part of a mission, like the chemical trucks in the PCP racket, is good too. I know some cars are scripted to be parked at locations in various missions, but I don't think we need to mention all of those.