This matters more now that England's Renters' Rights Act lets tenants challenge rent increases they believe are above market rate. The problem is there's no easy way for a tenant to find out what market rate is. Also, now that landlords can no longer accept offers above the asking price, they have an incentive to list higher than the rent they expect to get.
That's what inspired us to build RentBench, a platform where renters anonymously share what they currently pay and can see median rents for their area, so they can quickly check whether a price is in line with the market instead of spending hours going through listings. We also include official ONS rent inflation and median rent data for context.
It covers Great Britain for now, but we'd love to expand to other countries if people find it useful!