I can share a few insights How your data appear on reports may differ depending on the type of reporting you use.
Purchase Order reports are vendor specific reports which focuses only to one transaction. You will see positive amounts in there because its main purpose is to sum up all transactions created for suppliers.
On the other hand, Custom Reports involves multiple transactions. QuickBooks uses negative signs to show a decrease in the total balance on the report. Even if PO's are non-posting transactions, they are shown as negative there since it's associated to a vendor name.
I'll be adding a few related articles below to help you understand reports in QuickBooks and how to customize them:
Let me know if you have other questions or clarifications about QuickBooks or this topic. I'll be right here to help you whenever you need it. Have a lovely day!
