If you want to keep the car for a very long time, do it right but don't expect to get any change in you pocket from $40-50K. If you are going to use the car and then sell it in a few years then by all means go the cheap route and save money. Don't think using a mig welder on panel steel is a good job (it is like using a flame thrower to light a candle) the only way to go is TIG or gas welding. You will get what you pay for. In the long run quality does not cost - it pays. I spent NZ $40k on my panel and paint 15 yrs ago. I stripped it to a bare shell and then some. I had it soda blasted EVERYWHERE!!, I had panels hand made (repros were crap) I replaced the bottom of the doors and my front 1/4 panels with stainless so they will never rust again. and the list went on. All hammer file and finished I.E no bog/filler, 2 pack Spies and Hecker paint. Real panel beaters are a dying trade these days most of the new guys are panel replacers and glorified plasterers. My 240z looks as good today as it did 15yrs ago when it was finished after 3 years in the panel shop. When you choose the painter have a look at some of his previous work and ask other Zed guys for advice on who to use. If your budget allows, use a classic car restoration shop as they have the expertise, tooling, knowledge and know who are the good painters. Prep is 95% of the work and the gun is 5%. There is no fast, good and cheap option. All the best