Takes money to make money I guess. I am saving over $2,000 a year on interchange fees. This was done by having my merchant classification code corrected -- my processor had it wrong. I also switched to cost plus reporting. I started settling within 3 days on most of my store's sales, and I fixed an AVS issue. My processor was not very helpful until I pointed out some of the stuff in this book. The cs rep was embarrased. You can buy it on Amazon, just do a search on "understanding interchange". Good business advice: don't be afraid to spend money.