just kidding, and I wish I had that much to spare... lol.
i'll wipe after each throw, and with the older stuff, I bath with hot water and soap every few weeks, usually after I can tell it's time. my experience, the games may vary from ball to ball on exact maintenance schedule, but typically i'll only resurface after I can tell the bath won't do much any more, or the power is lacking that much from the pocket hits.
alcohol will harden the surface of a ball, and decrease it's ability to grab