When it comes to discounts on an invoice, you have 2 possibilities: adding a discount amount or adding a discount percentage
Adding a discount amount:
Create the discount item in your "Products and services catalog" settings as follows:
Name the discount item (i.e. VIP discount, etc.)
Under "Price", enter the amount preceded by a "-" sign.
Under "tax", choose "taxed" and save
In the invoice :
Add the discount item to your invoice like you would for any other product.
The amount of the invoice will reflect the reduction in price.
Adding a discount percentage
Create the discount item in your "Products and services catalog" settings as follows:
Name the discount item (i.e. VIP discount, etc.)
Under "Price", enter the % amount preceded by a "-" sign: for example, "-0.1" for a 10% discount
Under "tax", select and save
Add your discount items to the invoice as follows:
Make a note of the pre-discount amount included in the sub-total line (i.e. $2000 as per the example below)
Add your discount percentage item
Enter the pre-discounted sub-total in the quantity (i.e. 2000) and "select"
