Problem: How
...
to add Discount
...
to
...
Customer Order / Invoice?
Solution: Use discount type settings as shown.
1. Go to Discount Types - Sales > See also > Discount and Markup Types:
2. Create a new discount type, press
...
Save and close:
3. In the Customer Order Main tab, select the needful discount type 
at Main tab:
4. Refill prices option enabling will be demanded if you want to apply a discount to an already posted Customer Order, but please mind that if .
NOTE. If you enable the Refill Prices option you’ll , you need to enter Prices again.
For automatic discounts setup please refer to the link: 3.3.2. Automatic Discounts and Markups, 3.3.3. Automatic Discount Conditions
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