I just want to leave a message and say thanks for all the tips here! I for sure used alot of them and it was a great help. As for change though, depending on your items I'd recommend more than $60 in change.
What we did was we had $150 in change (50 1s, 20 5s) and by the end of our thursday space we barely had much 5s left. Almost every buyer had 20s (some even gave us 100s!) and the break down in 5s is the best way to go about them as you will by far have 20s by the end of your selling.