need ability to add extra shipping and handling charge

The ability for us to to add a S&H Charge to a "rate browser" shipment or manual order is important. For example, we want to be able to charge $3.50 S&H to each shipment above and beyond the negotiated UPS/FedEx rates. This would be used when we have a walk-in customer or manual shipment to process (not an e-commerce order).