Any metal can be coated, even galvanized, but the finish on the powder-coated galvanized parts will not be as good as clean metal parts. I plan to powder-coat all TOAD's iron work in white. This removes one of the most difficult problems in building traditional boats. Gathering all the parts to be galvanized together at one time in order to meet the minimums. Sometimes this just can't be done.
Some parts have to be installed before others.
Oh yes, the Eastwood home powder-coater. I don't think this is good value unless you are going to use it for a long time and do a great many parts. I think I'll stick with my local customer powder-coater.