This is mainly for new sellers who will probably not know about this, but I may be pointing something out to some more advanced sellers as well. When an auction ends, and sells, it gets placed in the 'sold' section in 'My eBay'. If you have many of the same item then you may be interested in this.
If the auction had more than one bid then you can send a second chance offer. This means you may sell a second item to the last bid that lost the item. You will be selling it at a lower price, but you will not be paying any insertion fees.
You don't just have to sell one item on a second chance offer, you can sell as many as there are bids from seperate buyers. But remember you don't guarentee a sale.
Here is an example of how it works:
You sell an item for $200, but it has more than one bid, and you have two items available. Instead of listing the second and waiting a week you could send a second chance offer to the person who lost the item. He then has the opportunity to win the item.
Please note, you do have to pay the final value fee on any items that sell on a second chance offer.