This is my 1st post and thought I would try and give you my personal experience with boat painting. 2 years ago we painted my Supra ski boat with Interlux Brightside paint. We first tried spraying it as my buddy works at Jeep and has a lot of experience with body/paint work and has his own paint shop in his garage with a ventilation fan. The Brightside paint just would not go on evenly, it would sort of "bubble up" everywhere. We tried different mixtures of thinner and the stuff just would not go on smooth. He said that this was the worst paint he had ever worked with.
We then decided to roll it on with a foam roller and this was better. We really didn't use a brush and do the "tip" method as you have read about. We just kept rolling over the area until it looked good. We had a good coat of the Interlux primer on there but we had to keep going over certain areas that just would not cover. It was yellow paint so that was part of the problem but it just didn't cover like it should have, whether it was yellow or not. We mixed everything to the exact specs of Interlux but it just seemed too thin.
I'm not sure what model of Interlux you are planning on using but I would highly suggest NOT using Brightside. I had read some decent reviews of it so I thought it would work well. If I were you and going through all this work I would find out what other people use and spend more money if necessary as I'm sure you don't want to do it over.
I will say that I have had quite a few people say how nice the boat looks and they can't believe that we rolled it on. I'm much more picky when it comes to painting so I'm not very happy with how it turned out after all that work.
My buddy said we could have used some of the high-end car paint that he knows is good stuff since the area we were painting was mainly above the water line. I believe the name of the stuff he suggested was Centari and it is made by Dupont. I don't know if this is the best way to go or not(car paint vs. boat paint), just wanted to give you more ideas. That stuff was about $75 a quart but would have been worth it to me. Good luck.