Most powder coaters will have a furnace to blast off all the oils etc. , and will then sand blast every part before even starting.
This silver frame looked like #$%* before, I did nothing to it before dropping it off

This frame, swing arm, triple tree, kickstands, gauge holders, and all the other misc pieces was $400.00 CDN......about $360.00 US.
Done in Nanaimo B.C. Very happy with results