Hello, @BTLAK.

Let's figure out why you have negative inventory quantity on purchase orders when pulling up reports and guide you in fixing this to keep your data accurate in QuickBooks Desktop (QBDT).

Negative inventory is caused by entering sales before entering the corresponding purchase transactions. For example, you sell inventory items you don't have in stock. Sometimes, miscounting the quantity you got from your vendor and being unable to convert your purchase orders to bills can cause negative quantity value on reports.

If your first transaction(s) for an item is sales, sold inventory items without recording purchases, or entered purchases or adjustments before entering sales that cause negative inventory quantity on inventory reports, please see this article's How to fix negative inventory dropdown for the fix: Fix negative inventory issues in QuickBooks Desktop. Before doing any of the steps, make sure to back up your QuickBooks company file and consult with your accountant to assure that these changes are legitimate. 

Also, QuickBooks updates inventory quantities and value as you track every purchase and sale. But sometimes, you may have to record an adjustment to keep your inventory status accurate. To do this, check out this article as your guide: Adjust your inventory quantity or value in QuickBooks Desktop.

I'll be around if you have other reporting concerns or questions about managing inventories in QBDT. You can comment below, and I'll gladly help. Enjoy the rest of the day.