i 2nd getting a powder coating. if your son does not like scratches on his bike, then it is VERY difficult to get an amateur paint job to resist scratching. as someone who has done it several times, with layers and layers of primer, paint, and clear and sanding and sanding and sanding between coats, it's just NEVER going to be as durable as a paint job that is baked.

i fear that if we are doing this because of a scratch, the paint will come out looking beautiful and it is going to get a scratch it in within a week if it's used with any regularity.