First of all, you've got to make sure you've got a product that's in high demand.
Let's use the HammerTap market research tool to compare two items we might want to sell on eBay. Let's say we have found a great source for golf clubs at deep discount. A golf store is closing everything out. Or, a drop-shipper you know of bought an entire semi-truck load of golf club sets. They just want to clear them out, so they offer you any set of golf clubs for $200.
The illustrations below show for how much you can expect to sell Nike and Ping golf club sets.
From the data shown above, we see that Nike golf club sets sell for more than Ping golf club sets. To be exact, on average, you'll get $25.52 more. Whether or not you know anything about golf, you now know you can expect to sell Nike clubs for more.