Some order options have a Setup Cost and / or Per Unit Cost. Setup Cost is a one-time charge regardless of quantity. Per Unit Cost is a charge applied to each quantity of your selected item.
For example let’s say you are looking at an item that has a base cost of $1 per unit at a quantity of 200 ($200 sub-total). You select an order option that has a Setup Cost of $10 and a Per Unit Cost of $0.05. Your new sub-total would be $200 + $10 Setup + ($200*$0.05) Per Unit = $220.