This module allows Zen Cart stores to add a fee or discount to an order based on the payment module selection. It works with the default Zen Cart checkout system, Fast and Easy Checkout, and Fast and Easy AJAX Checkout.
As certain payment methods add fees to the seller, you can charge similar fees to the customer and organize them by payment method (PayPal or credit card). Alternatively, you can offer a discount to customers who select a payment method other than PayPal or credit card. Both scenarios will work well within this module.