Hi,
If you have items that you sell multiple quantities of you can create an entry for that listing in the Product Master tab.
In the settings you can choose to link the sold items to the product master through either the Listing Description, or through the SKU.
If you match them through the SKU you would put the SKU into the eBay listing itself, and when the item sells we get that information through the API.
If you havent previously setup your listings with SKUs, you can set them all at once in MyCostPro using the Active listing tab.
I hope that answers your question, let me know if I missed some detail of it.