A site like this does not get off the ground in the U.K. without the cooperation of the letting agencies. The primary web-site for finding rentals in London is

A site like this does not get off the ground in the U.K. without the cooperation of the letting agencies. The primary web-site for finding rentals in London is rightmove.co.uk and zoopla which are both owned by the letting agencies. Of course they want tenants to bid against each other to try to extract the maximum price for properties.