In order to track inventory in the manner that you require, you need to use QuickBooks Premier. Unfortunately QuickBooks Pro and QuickBooks Online do not track backorders which is what you need. In addition, you can also run an inventory stock status report by item or by supplier that will provide you with your onhand status versus what you have on order from your customers.
You can learn more about QuickBooks Premier here:https://quickbooks.intuit.com/desktop/?highlight=premier.
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