I was at a body shop a couple of years ago and noticed an old Bronco in for replacing both quarters. I asked the owner how much he was charging (no paint work). He said $1000.00 for the pair.
I knew I couldn’t afford to pay for all the work I needed so since then I have $480 in a nice mig welder. I have replaced every panel on my ’55, the back end of a ’67 mustang, and have done countless projects for myself and friends. It’s definitely paid for itself many times over. Others may comment on body work costs, but for me the hobbyist, I wouldn’t touch a quarter replacement for less than $250 and that’s gotta be cheap. It just wouldn’t be worth my time unless I did it free for a friend. Even doing it myself there’s the $400-$600 for a quarter, paint supplies, sawzall blades, drill bits, grinding wheels, wire wheels, gas, wire, electricity, time,etc.
I like to fully prep, repair, and paint the area under a removed panel. This is something you probably won’t get from a shop if you’re on a budget. Probably wasn't the answer you were looking for, but just something to consider if you plan on doing alot of this in the future.