If a mechanic has a hangar the painting could be done right there. The mechanic removes the control surfaces. You strip. The auto painter comes to the hangar and paints. A special paint booth is not needed. I painted my C-210 without one and I have seen many planes painted in regular hangars. A simple hood and airline provides safe breathing air (costs start at few hundred dollars).
Remember, I an amateur, actually stripped and painted my plane by myself in 1981 and the paint is still in good so I do know what I am talking about. However, if somebody does not want to do something the excuses are endless.
If specialty shops charge $15K to paint and I can do it in 3 weeks for $3k and that $12k saving is like tax free income. Now you figure $4000/week tax free which in my tax bracket (Fed + state + FICA) exceeds annualized $400,000 taxable. Good cowboy wages. You plug in your own numbers.
But, as I said, almost nobody reading this would even consider trying. It's the city slicker syndrome. We country hicks are consummate DIYers. We have to be.