Tip to Piano Tuner/Technician in the US?

[kayleez]

Hello,

I live in the US now but not from here. I have never got used to or figured out the tipping custom here...when to tip, how much...It is all just so confusing.

So I just bought a piano, and supposed to have it tuned soon. The first tuning is complimentary with the piano purchase. Then according to the common tipping courtesy, should I tip my tuner? and if so, how much? for the first free one as well as the following normal paid ones.

Thanks!