Barter Deck will enable shoppers and retailers to negotiate product prices through a mobile app and web widget. The goal is to give retailers powerful price discrimination tools while letting customers buy items at affordable prices. Shoppers can make offers to retailers, who can accept, deny, or wait to accept later. Denied offers will be shared with other registered retailers. This creates a marketplace where negotiation supplies both demand and supply. Barter Deck will initially sign up retailers and later add consumer tools to generate a full marketplace for negotiated retail prices.