Very few individuals have taken on the cost of properly re-powder coating a cage as it is commonly more expensive than obtaining a new cage from what I have been told.
First, find a Powder Coater that has a heat chamber large enough to fit your cage sections. Costs vary greatly by location and competition.
It'll be expensive, I had items redone before and they have to bake and/or blast off the old coatings before being able to apply the new coating/s.
Last small powder-coat job I had done cost almost $1k AUD, that kind of money starts getting you into stainless steel cage territory. I guess cost will depend on where you live or if you can do it yourself maybe but in my situation it was certainly not cost effective as a replacement cage cost me less than $500 AUD.
I asked about redoing a cage. I'm in the UK. I think they wanted to know the sizes to give me a quote (they didn't seem to completely understand that it was a cage). I seem to remember it was a little over £400, which just wasn't worth it. Brand new the cage was about £180.
If your cage is a good solid one that were widely available up to recently then I would seriously think about doing this. I have a right carry on trying to get a cage here in UK.
They seriously are not what they used to be. The main structure of the cage is now very thin. The doors are very narrow.
I had two delivered damaged which didnt look to be transit by the carton and then the UK distributor said get lost its not viable to us to send another. I didnt want £20 off and a cage hardly fit for purpose I wanted what I had ordered.
So take care if it is a good one consider your options.
Agree, unless you know someone in the business and has the proper equipment and curing ovens, trying to refurbish ( strip and re-powder coat) a cage of appreciable size doesn't seem viable. Heck I do know someone, and getting motorcycle parts done ( and not big ones) is stupid $$, I only do this for clients with deep pockets.