They all offer the facility to view several lease deals from different providers.  Their value algorithms are based on data that was previously populated on their site.  It doesn’t search the net to compare prices that were advertised elsewhere.  As not all Dealers and Brokers advertise on every lease car comparison site, some don’t advertise on any, so it’s always best that you research as many companies as possible to find the best deal.  As many providers have access to similar deals, we recommend that you research the company and read their reviews, placing your order with a service provider that you feel you can trust.