I've just got mine back from getting done this weekend.
I've got 18" Rays on my GT model, and I had them done in a gunmetal on my silver Z - yes I know..... once I get the rest of the car washed next weekend, I'll post some pictures.
Anyway:
I had the wheels on my BMW M refurbished, and paid about £65 a rim, but it involved sending them off and getting them back a week later etc. etc. etc....
This time I gave the car to a bodyshop and got them to strip the wheel front and, prime it, and spray it..... and it worked out at £45 a rim, and I was able to pick whatever colour I liked.
The point I'm trying to make is that you need to make sure you're comparing prices for what you're getting for your hard earned cash, and not be comparing apples to pears