1. A method for providing an interactive seat map showing locations of available tickets in an event venue, the method comprising: receiving, at the client computer from a network-based system, a base map illustrating locations of sections within the event venue; receiving, at the client computer from the network-based system, a coded image map for building a map overlay comprising a polygon for each section depicted in the base map; receiving, at the client computer from the network-based system, an inventory for an event at the event venue, the inventory providing, for each section, section data that includes available tickets for each section within the event venue; displaying, at the client computer, the interactive seat map by loading the base map and building the map overlay on top of the base map so that each polygon of the map overlay aligns with the respective section of the base map; determining, at the client computer, one or more characteristics for each polygon of the map overlay based on the received section data corresponding to each polygon; applying the one or more characteristics to each polygon of the map overlay; and linking each polygon of the map overlay that includes available tickets to the section in the inventory.