If you are only in for the summer I wouldn't paint it. My boat is 20 years old now, never painted it. I pull it out of the water each month for a couple of hrs , spray on bleach, rinse, grease the outboard pivot joints, change kicker oil and clean off the zincs. Then back in the water for another month. If you get it out in 4 weeks you never have to scrub and no barnacles.