As said above there are way to many variables if your concerned about being ripped off inquire locally about reputable shops in your area. I know shops that use a lot of plastic for body repair and it cuts down on the time quite a bit and therefore costs less in most cases. I also know shops that have skilled bodymen in them that have been in the trade for years and can work metal to a point where they use little or no plastic filler, even on very heavy damage. You will pay more in most cases for work like this obviously. I have also seen MAACO paint jobs that look pretty damn good and jobs coming from a "professional" shop that look like crap. Any shop you go to is only going to give you an estimate anyway they are not going to give you a flat rate on the time it takes to finish a car/panel etc. You have to consider "what lies beneath" also there are a lot of things you cant see under paint and in between body panels that could possibly add to the total cost. With that being said why not just find a recommended shop or two in your area and get a good faith estimate and if its within your budget do it, if not find someplace else.