[x-bird]

If you have an air compressor and your own spray guns, lowest cost DIY method is to get some Rustoleum rusty metal primer and mineral spirits (not thinner or acetone) to thin it with. Tubing eats up massive quantities of paint. one quart will do your whole buggy for about $20 including the spirits. If you go rattle can, you'll spend close to 40-50 bucks just priming it with two light coats. Likewise color coat, rustoleum in the can with mineral spirits, unless you use the hammertone finish, which needs xylol to thin it. Total price should come in around $50-75 once you add in some strainers, air line filters, and mixing pails. Rattle can will cost you over $100 just for the paint by the time your done.

Powdercoating is more durable, expect to pay between $250 and 500 for a whole buggy, and the low end is for one that's perfectly stripped and doesn't need blasted.

Automotive paint job will cost as much as you paid for the buggy, even if you DIY it.

If you have a lot of clean stripped tubing and only a little that had rust, use rustoleum's clean metal primer (white) and buy a rattle can of the rusty metal primer to hit the pitted areas with.

I prefer to strip everything off. No worries about adhesion, paint reaction issues etc.

As far as prep goes, i found a flat 5 inch velcro-backed disc in my drill with 80 to 120 paper. Strips tubing to bare metal in no time flat. around the welds and in corners i use a combo of 3m paint and rust stripping wheels (black nylon mesh with grit embedded) and an old 3-inch wire wheel that i got in an auto body jobber supply shop that the wires are set in a yellow, near urethane compound. I've used it for about 20 years on 5 car restos, 2 buggies and countless other projects. it doesn't shed the wires like other ones do. If you can find one, grab it! After a while of use, reverse the drill direction and it really tears deep into the weld layers, when it's not as effective, reverse it again.

Final prep, i've found isopropyl alcohol (rubbing alcohol from the drugstore) to be a great and cost effective cleaner, one wet wipe cloth followed immediately by a clean dry cloth. no residuals and no fish-eyes etc. no nasty smells, sterilizes flesh wounds to boot!