As a sub-contractor working for multiple audio/video retailers, when they send me on an install or service call I sometimes up-sell the customer into new equipment. The retailer pays me a 15% commission of the net profit on the sale. I would like to be able to have RepairShopr figure the commission if I have input the retail and cost information about the equipment into inventory. As an example, I sell a Sony ES365 projector for retail of $10,000. The cost is $6,708. The retailer thus owes me $493 on the invoice I would like to have an easy way to do this.