I must have lucked out. My watchmaker is pretty awesome. Sometimes when I have a watch authenticated, he will size it for free. Sometimes he will even do a light polish on it gratis. All for $20.
One time he forgot to charge me, because we were having a detailed conversation about ETA and such. When I found this out, I called him up and said that I don't need to pay because he forgot to charge me. I paid his wife anyway the next time I was around.
Downside is that he is grumpy at the start of the day.