Add Discount & Extra charge

To add a discount and(or) an extra charge to a payable, click on the payable code:

It will open the payable details page.

Click the "Discount & Extra charge" button:

Enter the required value and click "Update" to apply changes:

To add the discount and extra charge, you can also click on the "Update" button in the payable row:

And then click the "Discount & Extra charge" button on the opened update page: