UD:
It's coincidental, your story, since Saturday night I did a pool side house party in Deal, NJ and, like you, I was given a $100.00 tip at the end of the night; the hostess came to me with a cash envelope and said "here, there is a little extra for a great job". Thinking that it probably was a $20.00 tip (the usual), I never bother to open the envelope until I got home, only to find the extra $100.00 plus the $600.oo I charged. It's not just the money, but also these gestures that make this pofession worthwhile. However, I feel that I deserved every penny I earned, since the heat and the humidity were "excruciating", the thermometer hit 103 that night, even my amp was “acting up” due to the high humidity. I am still recuperating from that gig .
Your comment on starting 5 minutes early and going the extra 5 at the end is right on the money, I’ve done this many times and got rewarded for it. It’s a small investment that goes a long way. I also try not to take brakes unless I feel I need it, or if I do, they are usually no longer that 5-10 minutes. I also put a CD and keep the music going(softly) during this time; people won’t miss you as much.
When I used to perform with my guitar, it was “imperative” that I took a 15 minutes brake every 40 minutes, otherwise I would get cramps in my hand (something that eventually turned into “Carpal Tunel syndrome” and ended up with surgery). Now playing the KBs, my hands can go for hours w/o rest. What a relieve.

Mario