Every sales job I've ever worked at (and I've worked at a lot), I've always been a little paranoid about making sure the money I'm paid for my commission is correct. Sometimes my paranoia was warranted, sometimes not, but why take the risk? I used spreadsheets to keep track of my sales and make sure my paycheck had the right numbers on it. This way, when I said my numbers were wrong, I had the math to back me up. My spreadsheets are simple and easy to use, customizable, and if you have a particular sales situation I don't have a template for, I'll happily make one for you.