With respect to the hull below the waterline. The people who owned the boat before me docked it so they painted the bottom with an anti-fouling paint that is faded and has a rough texture. Since I trailer in and out I was going to sand it off and refinish and wax the bottom. Someone told me that the boat will actually go faster with a slightly rough surface below the waterline. Is this true?
It won't go faster with the bottom paint you describe above. You'll be fine if you just remove the bottom paint,Etc. The bottom paint can be some nasty stuff to breath so protect your lungs from the dust.
