just a reminder and tip - get familiar with ebay's listing fees. they have it where when you change from one group of starting prices to the next, you pay more.
Ie: if you start an item at $1.00 you will pay 35cents insertion fee, whereas if you would have started it at 99cents, you'd only pay 20-cents.
you'd be surprised at how many people start an item at $1 instead of 99cents and end up spending 15 cents more for their ad in order to get a penny more in selling price. For example, there are currently 4,108 items that have "dvd" in the title that started at $1.00 That's $616.20 in fees that ebay got solely because people started their items at $1 instead of at 99 cents. And that's just the tip of the iceberg.
http://pages.ebay.com/help/sell/fees.html
Of course, if your doing store listings, it's totally different. stores pay a fixed insertion fee.