Thanks for getting back to us, @Ffraga. 

Yes, you can set up a 10% discount on the vendor's bill to offset the remaining balance. Let me show show you how. 
 

1. Go to the Vendors menu.
2. Select Pay Bills.
3. Select the vendor bill.
4. Click the Set Discount button.
5. Enter the Amount of Discount.
6. Select the Discount Account.
7. You can click Add New if the income account is not yet listed.
8. Click Done.
9. Click Pay Selected Bills.

Paying bills is part of your usual accounts payable workflow in QuickBooks Desktop. To see the complete list of workflows and other vendor-related transactions, please check this article: Account Payable Workflow.

Please let me know if you need further assistance in handling your bills in QuickBooks Desktop (QBDT). I'll be here to help you out. Have a good one.