This is a simple method, if you don't know it, you will now. 1. Look on Amazon for products that are on sale. 2. List it on eBay at normal price with a postage fee. 3. When you get a sale, buy it from Amazon and send it to the customer as a gift which I believe means no fees paid too. 4. Profit with no keeping items yourself and having to send them yourself. Ensure the product has plenty of stock. Maybe have a fine print on listing stating 3rd party item.