Go to an experienced place. I made that mistake, and although it did not cost me anything but time, (they kept destroying my parts, and buying new ones). I now have my powdercoated fuel and water fills installed, and they are CHIPPING!! UGH!!!
Start with the small pieces first; to test his/their abilities. I do not think there are any differences between marine or other applications, but I could be wrong. If you are going to have the old stuff blasted off, be careful, as this can tear up your parts.
I am not sure on pricing on those items, but make sure you talk to someone that has his work already, and see how it holds up.