When you begin, this is the most daunting of all questions. I will answer it simply, but make sure you read the "Seling on eBay" tips for full instructions.

1. Research if others are also selling. Do a search on eBay and you will almost certainly find identical products for sale. Write down what price other sellers are quoting, dont forget to include Postage. Sometimes you can also copy other sellers descriptions, but I find it is easier to do your own. If other sellers are selling the same item, dont be discouraged, that just means that someone is buying it too. Sometimes you can find items that are not being sold, but make sure there is a demand first by trying one or two out.
2. Work out your Listing Costs - I cannot stress this enough. If your costs  are greater than your profit, then you are not making money.
   Your costs on eBay are simple, they are the Listing Fee + Final Value Fee + Any Extra Feature Costs.
3. Work out your Selling Costs - To find out how much the product will be, (including postage), just go to the wholesaler and add it to your shopping cart, then when you go to the cart you will see actual postage costs. (after this you can delete it from your cart, because you havent sold it yet). The wholesale price + postage is your selling cost.
4. Add the Costs together - This is your base starting price, anything over that will be Profit.

If you have done your research right, then all you have to do now is make the product just a bit more interesting than the others around it and you have a sale. You can do this in the following ways...

• Sell with FREE POSTAGE - this puts a Free Postage sticker over the image in your listing, so buyers know the cost.
• Sel it CHEAPER - I always undercut even the cheapest buyers, just to make sure they came to me. Lets face it, everything over and above your cost is PROFIT. But dont make your profit so small that it isnt worth your time. I usually only worked on about $15 - $20 per item, but for some of the bigger items $30-$50. It is better to sell 10 items and make $15 each than to try and sell one item with a markup of $150.
• Make it APPEALING - you can dress it up a bit, but make sure you always tell the truth about everything in your listings, then you dont have problems later. If you need to put more photos in, host them away from eBay to save costs.
• Answer Questions quickly and politely - people will more likely buy from you.

REMEMBER - look for products that you would likely buy, and sell them, becasue more likely others will want them too.

I became an eBay Powerseller after my first 100 sales in only 3 months just following these basic principles.

HAPPY SELLING!