Patchwork Art Fair!

My girlfriend and I have applied to be in the Patchwork Craft show in Santa Ana this May. We haven't received word that we've been accepted but the best strategy is to act as if we have so we can be ready. We are going to label all our stuff, and make displays. It is our first show. We will be sharing a booth. We don't have a lot of money, but we want to be sure to cover all the basics. We could get a cash register for about $100, but I think that we can do with out it this first time until we can get an idea if this will prove profitable and how difficult it would be to deal with out one. We plan on having aprons with pockets to keep cash in. I think this will serve. I want to get a calculator with a printable tape to give as receipts. This can be had for $15, which is more doable than the $100 register. It cost $80 each to apply and our merchandise ranges from about $4 to about $50. I figure people coming to a street fair style craft show are probably not prepared to spend more than that in cash any way. We could also get a credit card reader for our phones ostensible free when we agree to a processing fee for each transaction. Again, I would like to start simple and complicate things as we become accustomed to what we are doing. I plan on keeping my prices the same as in my etsy shop. I would appreciate any advice or stories of experience you guys may have.