Create a feature that flags a possible "error" if a lower price is offered as "Sales Information" vs. "Purchase Information". The trigger would be a lower price offered than your purchase price. The trigger will be a pop-up and will NOT let you proceed without checking the box. It will ask if this is "...something you really wish to do." This trigger may help catch mistakes made in pricing your customer incorrectly and giving them your cost, which I almost just did :-)