Prices can vary depending where you go, but as a rule, you get what you pay for.
My previous car had a poorly repaired passenger door. I got a straight, rust free replacement door with a view to having that repainted and fitted. We then found rust on the rear wheel arch, so that needed attending to as well by cutting it out and welding it a repair panel. The whole of that side was then painted, and to be fair was bang on.
I seem to remember paying in the region of £350 for that.