The small size of IPT vehicles gives them a number of advantages over commercial public transport. Vehicles load and unload more speedily, with reduced stopping time and passenger waiting, and can better negotiate congested streets. Paratransit provides a frequent and flexible service. Although some services operate fixed routes determined by passenger demand. The small size of vehicle and the possibility of starting with a secondhand one reduce the initial capital investment and place the enterprise within the reach of local private initiative. Typically, the majority of vehicles are owner-driven or 'hired' from family members, although there are instances where multiple vehicle-ownership and leasing have developed, or where individual owners group into co-operatives.