With more than $63 billion worth of products, the secondary market - also known as the liquidation or surplus market - can be a "gold mine" for online sellers in looking for the right stock to stay competitive. As a seller scales his eBay business, it is necessary to know where to locate quality sources of goods as well as how to successfully resell products to eBay purchasers.

The Reverse Supply Chain, which is composed of flow of retail consumer returns and overstock goods, is an increasingly developing business that fuels about $63.1 billion in the secondary markets and is in the hands of professional consumers like eBay Powersellers.

The reason why liquidation and surplus merchandise markets are growing is due to the 4 to 6% of retail merchandise sold every year that is sent back to brick-and-mortar stores and web merchants. Life cycles of goods have also decreased in value from years to weeks, or even months, in consumer electronics categories. Studies too have shown that the average U.S. consumer will struggle for several minutes just to get an electronic device to work before giving up and sending it back to the store. Furthermore, the federal government gets rid of an estimated 10,000 computers each week.

There are seven categories of secondary market merchandise, namely the New Assets, Shelf Pulls, Returned Goods, Used Assets, Refurbished Assets and Salvage Assets.

New assets are in their original casing and have all of the features as promoted by the manufacturer. Conventionally, they are overstock goods that were not sold in retail or consumed in any way. However, this surplus merchandise still has the manufacturer's warranty cards.

Shelf pulls were formerly in retail but were never sold. They normally have one or more price stickers and/or tags, showing several markdowns and have been exposed to consumer contact.
Because these goods are delivered via a reverse supply chain, there are possible signs of further handling. Shelf pulls may show various product and package conditions that differ from the initial manufacturing.

Used assets too were formerly available for sale and put into use. They have visible cosmetic tarnishes and defects, such as signs of age and scrapes. Since these items are generally pulled out from a working environment, they hardly ever come in its original package and include additional parts, accessories or documentation.

Returned goods were sold to a consumer, who later physically returned or mailed it back to a certain location. The returning of an item may be because it does not have any correlation to its utility. As a result, the item may be in good and working condition.

Refurbished products are used but they have been tested and restored to its working condition. Often times they come in their original wrapping and may include documentation, accessories or extra parts. And due to its operational description, there may be visible defects such as scratches and dents.

Finally, salvage items have been identified as damaged in its appearance, functionality, or both. They are mostly used as spare parts.