Pick up some of the books by Don Casey. Lots of good info in there. Get a West Marine catalog. Lots of cool stuff in there. Lots of other places to order as well. When I go to my local West Marine and ask a question they open the catalog. I can do that in my reading room. Lots of chandeleries on the net. Any local ones in your area? Also, when a product says marine its 50% higher than the identical product that doesn't say marine.
Gel coat can be repaired. Color matching isn't fun.
Find out what bottom paint is on the boat. it may not need complete removal to be repainted- just cleaned up. If you do sand the dust is hazardous. Protect yourself. Good mask and cover up. Marina may not let you do a lot of sanding there.