Hi Rickd,
Thanks for posting your question here. The quantity available for each item you are relisting through Auctiva should be tracked in the same manner as when you relist your items using eBay's standard listing tools so I expect this aspect of managing your listings will remain as you are accustomed to.
For example, if you originally posted a fixed price item with a quantity of 50 available and the item closed after 4 of the items sold, the quantity would be listed as 50 once again if you were to relist the item through Auctiva without manually changing the quantity.
However, if you were to post the same item with a duration of Good til Canceled, I believe that the quantity would not be adjusted back to the what it was initially when eBay automatically renews the listing every 30 days.
If I misinterpreted any aspect of your question, or if you need any further assistance with your account, please feel free to contact our Customer Support team by mousing over the “Help” tab and selecting the “File Support Case” option.
-Mike