Refinish Products - How many brands out there?
I'll add Sherwin-Williams and ICI/DuLux to the mix of manufacturers of automotive finishes. I'm more familiar with PPG & DuPont coatings. As another post pointed out, each manufacturer makes several lines of paint of different qualities, or for particular applications.
In my experience, pricing has been a function of the paint line used for the base, the particular color and shade of paint pigmentation, and whether or not a clear coat is part of the mix.