I have started taking lessons recently from an older gentleman that is a Berklee graduate so that I could improve my knowledge of chord structures and theory, as well as technique - just want to become a better player. So far a lot of what we are going over is nothing new to me, however there are things I am picking up and the direction we are going is exactly what I expected - I am saying that it is a good experience and I like the way he explains things. Anyway, that's not the point. The point is that he teaches out of a music store, I pay the store for the lessons, which in my opinion are pretty inexpensive to begin with, but I know he is only getting a piece of what I pay the store. I also know his only source of income is teaching and gigging and he isn't exactly well off. Is it proper etiquette to tip the instructor in a scenario such as this? I really have no idea what the proper thing would be. Is tipping an instructor normal at all? Would this possibly be against some agreement he has with the store? Could it possibly insult him to offer? And if it is proper, how much of a tip should I give him? Thanks for the advice!