I dunno, it was some hours, but I don't recall it being God-awful brutal long.

I don't know how much sandpaper

I used two different sanders: one a random-orbital that had been in an auto body shop rather large-ish rectangular thing, and also a palm orbital

I prepped the boat and then brought it to a friend who is in the industrial painting business as in, shipbuilding yard type stuff. Boat is 'Buoy Yellow' two-part something industrial, hell I don't even know what the paint is, but I expect it's an LP. It's been good paint.

My trimaran is AwlGrip.