I understand the general idea, my concern is more with items on sale. What is the easiest way to keep on top of item prices? It will be easy enough if you're only listing a handful but from my understanding to make any sort of real money you need to list hundreds, sometimes even thousands. Item sales constantly come on and off. If you don't pay attention I can imagine it's very easy to lose a lot of money. I'm presuming the majority of people will use some sort of program to automate the process. Can anyone recommend a good site/program to check out?