I'm looking to update eBay listings based on the UPC of my product. However, I'm able to use GetItem and include the tag in the xml request<IncludeItemSpecifics>true</IncludeItemSpecifics>, and I can dig the UPC out. I'm looking for a faster way of returning all of the UPCS of all my listings and I feel like GetSellerList should do that. I've read the documentation and it doesn't have the IncludeItemSpecifics, which makes me think it is not possible.
Currently I'm using GetSellerList, putting all the eBayid's in an array, then individually calling the information by using GetItem with IncludeItemSpecifics in order to get the UPCs. Is there a better way of doing this, or does anybody have a better tactic at tackling this problem?