Forgiving partly unpaid invoices

You have to issue a vendor credit memo for either the exact same expense item or to a "refund" type income account. If you want your books to show you spent 1000 to replace the TV then you have to claim the extra 200 income you are not receiving

Is there an easier way, as in creating a discount code perhaps?

Hello there, @MarioMP.

Let me walk you through creating a discount and add it as a line item on the invoice. 

Here's how: 

1. Go to List, then select Item List.
2. Click the Item drop-down arrow at the bottom of the Item List window.
3. Select New.
4. Click the Type drop-down, choose Discount. 
5. Enter the Description and the Amount or % of the discount.
6. Enter the Description and the Amount or % of the discount.
7. Choose which account in the Chart of Accounts will the discount be mapped.
8. Select the Tax Code of the Discount.
   • Taxable
   • Non-Taxable
9. Click Ok. 

To add them on an invoice, here's how:

1. Go to the Customers menu to get to Create Invoices window.
2. Choose a customer on the Customer: Job field.
3. Record the necessary items.
4. Enter the Discount on the following line.
5. Click the Save & Close button once you’re done.

For additional resources, check out these articles: 

• Add, edit, and delete items
• Create an invoice in QuickBooks Desktop 

 Please leave a comment below if you have further questions. I'll get them answered for you.