The power is in the Master child links, which links the Auction to the items and bidders and the Items to the bidders and winners, which are actually the same thing just presented differently.
There is also the power of the Queries that supply the forms, they can present the data in different orders, so the Winners form on it's own tab just presents them as they happened, but the one on the Item Dis form presents them with the last one at the top.
There is some fairly simple VBA to update the forms by requerying them etc.
It doesn't at the moment check if the Auction Item quantity is greater than the Item Stock Quantity but it can.
It could also control the Item stock level when you set the auction level.
Once the data is in there and you have the Auction you can then run analysis on what sells best and at the most profit, Who is consistently the best bidder etc.
How many more products could have been sold if you had more stock.