Why the eBay Catalog Isn't Enough
eBay vs Other Marketplaces - The Catalog
The main difference between Price Spectre and other repricers that support eBay is that Price Spectre was built specifically with eBay in mind. Other repricers are typically built towards product-based marketplaces such as Amazon, Alibris, and Abebooks. These marketplaces are built on a strong catalog that all sellers are required to list against. eBay is different in that sellers can list anything regardless if it has a UPC, ISBN, or other product code. eBay has spent several years building their catalog however the majority of eBay is still not cataloged. This is even more the case with eBay's international sites.
Because of eBay's relatively weak catalog this means that most non-BMVD sellers cannot use eBay pricing data when using most repricers. Price Spectre is however designed to be able to be used by all sellers regardless of what is being sold*.
Products Not in the Catalog
Except in a small number of categories, eBay does not require that listings be listed against the catalog even when a matching catalog product exists. This means that using a repricer that relies solely on the catalog may not return all relevant results.
While most listings on eBay that are listed against the catalog are correctly listed many are not. There also does not appear to be strong enforcement despite this being a violation of the Search and Browse Manipulation policy. There is currently no way to directly report this type of listing to eBay except specifying "other search and browse manipulation" as the reason.
Below is a prime example of a listing that was listed against the catalog but has nothing to do with the product. The UPC specified is 027075045002.
In the above case, relying solely on a product search would yield very bad results. The user would be forced to rely on setting a minimum price and filtering out anything below that. This would not work if the miscataloged item is priced above that. In our example the miscataloged item is $45 which is a reasonable price (depending on condition) for the product it was listed against.
The Solution - Keywords
Because Price Spectre was built with eBay in mind we were well aware of these issues. As a result Price Spectre has supported keyword searching from our initial launch. In the above example performing a search using the keywords "pentax k1000 50" results in the correct listings being found while filtering out the bad listing. Further refinements could also be made with advanced keyword searches and use of other parameters to remove potential false positives.
Catalog Support in Price Spectre
For those sellers who do sell in categories where the eBay catalog is well used Price Spectre can perform product searches based on the product ID (UPC, ISBN, EAN, and EPID). If available this data is fetched automatically.
* Due to eBay's restrictions on search listings currently in the Mature Audiences category are not supported.