Is it customary to tip your LBS mechanic? I just bought a what the LBS calls a "Pro Build/Tune" package for $250 where they assist you in assembling your bike. There really wasn't any "tune" as they said that was a different package, so they set might bike seat to the point of my hip and that was the "tune", but we took my frame that had both derailers on it, front rings on it, seat post on it and then we installed everything else. Wasn't sure if I should tip the kid. I did pay for another $400 in parts from them. Thoughts?