To add custom pricing rules for a customer, go to "View Customer" under "Outbound" and click on the customer you wish to add pricing rules for.
Go to "Customer Pricing Rules" tab:
You can apply Fixed Price or Discounts by product or category to any customer of your choice by adding the details in the respective fields. Only one rule can be applied to a product or category for a given customer.
Pricing rules set for individual products have seniority over rules set for the whole category.
Check "Show Discount" if you want it to be visible on the sales order screen, if not, the discount will be factored into the sales price visible on sales order screen.