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How can I find out if an item was bought using the "But It Now" button?
How to find if an item was bought using the "Buy It Now" button
If an item's listing type is FixedPriceItem, then it is fairly obvious that they had to use the "Buy It Now" button to purchase the item (you can make a call to GetSellerTransactions and find <ListingType>FixedPriceItem</ListingType> and <Quantity>#</Quantity>). But if the item is a Chinese auction it is a little harder to find the answer. In order to find if the item was purchased using the "Buy It Now" button, you need to make a call to GetItem and look for <SoldAsBin>true</SoldAsBin>. If this flag appears in the GetItem response, the auction has ended due to the item being sold to a seller using the Buy It Now option. This flag is not relevant for fixed-priced listings.