LOL, I did new car wash & prep back in the 70s. All we had was gasoline to clean up the sloppy assembly (it was a Ford dealer) and cotton towels for wiping it down. Actually, I never did delivery prep, that was reserved for the senior staff, so I'm not sure what he did to "polish" the car. Probably turtle wax, since that's pretty much all there was back then. That and "NuFinish".
Interesting how these threads vary between marque forums. In the BMW world, it's sacrilege to do PPF without first prepping the paint for thousands of dollars. In the Corvette C6 (older cars) forum, the majority believe that PPF is not necessary and is overpriced. Of course, full disclosure, most of those cars are garage queens.