A method of providing a best bid and a best offer to a buyer, including receiving one or more offers to sell a commodity according to a predetermined contract at one or more specified prices. The specified prices are adjusted based on shipping costs associated with a destination specified by the buyer. A best offer is determined from the adjusted prices. A source location is determined corresponding to the best offer price. One or more bids are received to purchase the commodity. A best bid is determined corresponding to the source location. The best bid is adjusted based on the shipping cost between the source location and the destination and the adjusted best bid and the best otter are transferred to the buyer over a computer network for display by a networked host.