I agree about the paint correction, that was a big portion of the cost for mine.
Below is a picture of my car with the vinyl graphics on the frunk/hood that went all the way to the decklid. The previous owner had applied the ceramic over the paint protection film (frunk lid) and over the paint on the roof and decklid.
Once I had the vinyl removed there was a definite ridge where the ceramic ended. My detailer was able to talk to the shop that did the covering a few years ago and get the residual coating off the car. We did paint correction where it was not covered with PPF and then applied a multi stage ceramic coating.
