I don't think there's ever been a great debate over calipers, haha!
It's easy to DIY. Lots of options for high temp caliper paint. Pro is going to run you between a couple hundred to double that, depending on how much you want to do. If you just take them your car, it's going to be on the high end. If you remove, clean and prep the calipers yourself, it will be on the low end.
Not sure you can do much to "refresh" them as the hot brake dust really embeds itself in the paint.
I did mine myself with the calipers on the car. It involved cleaning really well with brake cleaner and a wire brush, masking everything off, spray with high temp base coat, applying new decals, then high temp clear.
