There's wheel refurbs and wheel refurbs. Usually for around £40, they break the bead of the tyre to rim, put a plastic shield under the edge of the rim, and set to work with an orbital sander to 'sand' the damage out. Its then sprayed in the back of a van or workshop. Sanding the rim like this looses the profile of the rim, and the quality / thickness of paint is poor and quite thin relative to powder coating and certainly not as durable.
For double that figure, the rims are dipped, totally stripped and then any damage is alloy welded, and then reprofiled to the original, before powder coating.
The former is the cheap repair that many mid range main dealers perform to prep cars for sale; once driven off the forecourt they tend not to be interested how long it lasts. The latter is usually done when the wheels are sent to a specialist wheel repairer for refurbing.
I certainly know which type of wherl refurb I would go for...