Add option for additional area discounts to all decoration processes

Screen printing price tables have an option labeled, Apply discounts on additional areas which allows setting a percentage discount for additional areas that use the same process.

We need this for DTF, as not having this ability forces us to manually quote to match the pricing we have listed on ASI etc. 2nd and 3rd location decorations typically do not have all the overhead that gets associated to the first location. Furthermore, it creates an incentive for consumers to buy the added location. Thank you!