Bottom coat removal

[willy]

Hey as you all may know next week I'm picking up Fillet 1's boat. It's in the water at a marina, Fillet says he took off most of the old bottom paint that was on boat when he bought it, it was very loose and he got it off almost to the gel coat with a power washer. This season he put on a quart/layer of bottom paint himself. It looks pretty tight on it from what I can see in the water. I don't want it on the boat, that boat just spent it's last season sitting in a marina, trailer boat from now on. The marina will power wash any green growth when it comes out next week but I want to remove all of the bottom paint and have never worked with this stuff before. What is the best way for me to get that crap off and do I have to seal the bottom with something afterwards. Any advise appreciated