Bottom paint help

[rb437]

Ok so here's the deal. I have a choice between another season of sharing a boat ramp with a bunch of inexperienced, inconsiderate neighbors or I can rent a slip within walking distance from my home for $210.00 for the season. If I use the slip I need to paint the bottom. The bottom has never been painted before. I know some of you will cringe at the idea that I'm considering painting the boat, but that's what I'm considering. My questions are how should I paint a previously unpainted boat (sanding, priming?), and what kind of paint to use. I've done a little research but am a little confused by all the different kinds of paint. The boat would be in the brackish water of the mid Chesapeake Bay and be used weekly or at least 2-3 times per month. Winters will still be on the trailer. What do you guys think?

Happy Easter