Hi. We own a pack and ship store. Our customers drop off packages and print labels with us. We are currently use shipstation. We are looking for a solution that gives us a way to review all rates for a shipment for fedex, ups, and usps. However, we also need a way to programmatically add our service fee onto the cost of the labels. This fee is how we make money. Right now we just have to do math in our head when quoting rate to customer. Is there a way to add on our fee to rates displayed using your app? Thanks