In electronic negotiations, buyers and sellers are represented by negotiating agents and it becomes imperative for the negotiating agents to acquire user's preferences to be able to negotiate better. In this paper we present the design of a web based engine to capture a buyer's choices over time through a preference elicitation tool known as Time - Tradeoff sequence(TTO Sequence). Preferences thus elicited are used by buyer's electronic agents to negotiate price and date of movie tickets with cineplex owners. Further, we illustrate with an example that negotiation outcome is affected by the timepreference of the buyer. © Springer International Publishing Switzerland 2014.