@shafferm 

So frustrating that QB employees can't even differentiate the difference between making a loan and receiving a loan.

If you haven't already set up a 'Note Receivable - Vendor XYZ' other current asset account.  Assign that account to the payment made when you issued payment to the vendor.  Then, you can create Vendor Credits whenever you want to apply the loan/interest to a bill.  The Vendor Credit should have the following format: on line 1, enter the Note Receivable - Vendor XYZ other current asset account for the amount of the principal portion being applied to A/P.  On line 2, enter Interest Income and the amount of interest charged.  Save.  The Vendor Credit books the reduction in the loan receivable and the increase in interest income, both of which are offset by an A/P credit that can be applied to the vendor's bills.