I've found that wetting a panel with grease & wax remover gives it a temporary shine that allows me to look at it... and helps get the crud off too.
I wanted to paint the car quickly, then fix the door dent later. Obviously not optimal. In the intervening several years I have learned a lot more about body and paint. More than I want to, actually ;)
Time & aggravation is the big factor here. I have discovered that I am not a "natural" at it. Engines, drivetrain, electrical, all that stuff I've been doing for 30+ years. But body and paint is new and not very pleasant.
I would pay someone to finish at this point, even the 3 grand! The trouble is, nobody wants a large job when they could be doing several more profitable small jobs. And as I said up front, the one who agreed is looking for reasons to back out...