FWIW, I considering the same and so I asked the guys at Waterlust how much they paid for their finish work. They stated it was about $1,000. They recommended just driving it around from place to place once you’re ready for that step and see what you can get.
Varnish can be hard, especially if the temps are extreme. I found that I got the best results from thinning higher than 10% (which tends to be the upper end). And then I just applied more coats. Another approach I saw was ‘wiping’ the varnish. It takes considerably more coats, is a bit less known technique.
Good luck!