On the "Modules" - "Order Total" page, you have the option to set up a markup or discount when a customer chooses a specific payment method during checkout. To do this, find the field "Payment Type Discount/Additional Charge" in the list and click the edit button in the "Action" column next to it.
A settings window will open:
To ensure the configured discount or markup works, make sure the "Enable module" switch is turned on. The "Sort order" field determines how this module will be displayed in the list.
Please note! The sorting order of this module must necessarily be lower than other modules, except for the sorting order of the "Total" module. Therefore, we have already set the necessary values.
In the "Discount/Additional charge" field, you need to specify the amount or percentage by which you want to change the price. If you want to apply a discount, enter a negative value (-10%, -200); if you want to apply a markup, just specify the amount or percentage of the markup (10%, 200).
You can also specify a "Minimum order amount" to qualify for the discount or markup.
In the "Payment method" field, choose among the available payment methods those for which you want the discount or markup to apply.
If you specify a discount, the phrase "Discount on selected payment method..." will appear on the order checkout page; if you choose a markup, the phrase will read "Additional charge for the selected payment method...". In any case, you can change this text to your own on the "Modules" - "Languages" - "Language Editor" page, more details can be read via this link.
Additionally, you can configure whether to include taxes and shipping in the calculations. If these switches are turned on, the discount/markup will be calculated based on the amount including tax and/or shipping cost.