In All Orders you can preset customer discounts using Price Levels. Prices that are applied using price levels are applied on an item by item basis. You view the standard price and discount percentage on a sales order by CHECKING 'View standard price and discount %' in Sales Order Preferences. Changing the discount percentage will change the price accordingly.
You can also apply discounts on the entire order using the Discount drop down list below the item grid. Before you can use this feature, you must first set up one or more discounts. You set the discount by percentage and amount.
One of the frequently asked questions about discounts is the affect of applying a discount on an item by item basis or the entire order. Other than the way the discount may be presented to the customer, the primary difference is how discounts are tracked particularly in QuickBooks. When a discount is applied on an item by item basis, the sales by item report will show the NET price charged to the customer. When the discount is applied on the entire order, All Orders uses the Item Discount so that the sales by item report will show the GROSS price. The discount item will show total amount of discounts applied to all the orders.