Lots and lots of variables here to say the least.
You can say that again. I've painted about 20 vehicles in my life and it is def a lot of work, especially the prep. Then there is the quality of the paint. My paint jobs tend to be pretty basic but I do spend the time on the prep. One of the marks of a good paint job is when you can't tell it's a re-paint. I can still remember going to a high end paint place with a Mercedes 300D for a quote and the guy was very tactful in explaining to me the the car wasn't worth what his paint jobs cost . I read about a guy in Beverly Hills more than 20 years ago that charged $75-$100,000 for a paint job. One of his criteria was that you could see a reflection of your thumbprint no matter where you placed it on the car, including inside the door jambs. He also built up and sanded off so much that it typically took 5 gallons of lacquer to paint one car. He would build the gaps on the door jams so they were identical on both sides.
My last paint job was the first one for me using HVLP, I'll never go back to siphon feed!