I have used this free material
https://www.corona-materials.de/en/material-library/car-paint/advanced-car-paint-xpr/235, which is a very nice car paint material with flakes and an optional cloth preview and created 15 real-world Honda car paint colors. They are named using Honda's actual paint names. These materials do not include any imperfections such as bumps, scratches, fingerprints, etc., but you can easily add them. These paints are set up using layers and masks for each layer. Very effective.
Later I want to compile an automotive pack with rubber, chrome, glass, etc. I'm sure when Corona ships, we'll see packs like this using the future node system, but until then these may help someone out there. i know I've taken advice and files before, so here is at least one back. Enjoy.