Just get a regular
cleaner, one that does not dull the ball, to use after each series. As far as keeping the
polish up by hand, you can't really get the proper finish without a spinner. I would probably have the
polish touched up every 20 games or so.
Resurfacing is generally a more in-depth operation. They will take a ball down to a very low grit (500, 320, 220) and sand it down to remove surface scratches, etc, then bring it back to the condition you want (usually box condition). Price around here would be 15-20 bucks. Usually only necessary when the
Track of the ball is getting very worn, lots of nicks/scratches, etc.
Refinishing usually just involves "refreshing" the ball to a certain grit/
polish level, and could be anywhere from free to 5 or 10 bucks.