+1 on PPS
If you are going to run a paint system that has limited cross link time between coats, PPS makes it realistic. The ability to purge the air from the inner liner and run in any orientation is huge as well. I used a C.A. Technologies setup and it was good to work with, the expertise available over the phone was even better.
When I was painting large sections, I tied in a second portable compressor to my shop unit. The extra 6 Cfi was probably more mental than technically necessary, but it allowed my desiccant air dryer some regen time. It’s a cheap way to add temporary capacity. Regulate as close to the gun as possible, short lines, gun filters, use good regulators. Lots of people have good luck at HF, but why rely on luck?
Painting was frustrating, but really rewarding at the same time. Spend the money, buy a good filtered forced air respirator. Above all practice. Not just mixing, spraying, but choreograph each work session, and how to move around the current work.