paint or powder coat?

[79 Camaro]

The company I used to work for started powder coating almost 30 years ago. We build packaging machines using a lot of cold rolled steel bar stock and sheet metal.

We learned a number of things over the years in regards to making powder coat stick.
1. Again prep is key. Steel stock is coated with some type of rust preventative and it has to be completely removed. We have a wash bay to clean the metal.
2. Sharp edges knocked down.
3. Don't use lock washers that bite into the powder and crack the powder. That's where the rust will start. Use flat washers and Loctite. When you install the washers most have slightly curved side and the other side has a bit of an edge. Install it with the curved side to the powder coat.

Yeah trailer hitches here in MN almost always rust due to all the salt. I guessing if the hitch was sand blasted before powder coating it would stay nice looking much much longer.