Everybody is probably telling you 4-500, right? Option 1: Take the cheapest estimate and go to the next shop, they should offer to beat the price. Continue until you get the lowest price possible. Option 2: buy some and do it yourself, it isn't always the best looking or longest lasting, but when you're talking 30-40 instead of half a grand, it's worth it. Option 3: ask someone who has had their car done or ask a dealership where they do it. Often times, you can find somebody that can get you a deal, especially if you offer to send friends there. They are already making a killing off of your car, but the more business they get because of you, the more likely they will be to give you a discount.