Consumer Focus said most people renting in the private sector had little information available to them before they signed a tenancy agreement.

Landlords, meanwhile, can ask potential tenants for references, deposits and other personal information, it said.

The group wants lettings agents to follow the example of sites like eBay or Amazon which give customer feedback.

'Massive outgoing'

Consumer Focus said it had written to some of the largest letting agents in England asking them to look at how they could use the internet to encourage more feedback about landlords.

In a survey of 2,000 people carried out in January, it found nine out of 10 tenants thought such a website would help them make better decisions about who to rent a home from.

"Currently the landlord is firmly in the driving seat despite rent being a massive outgoing for many of us," said Claire McAnulty from the group.

"People often sign up with little more than a gut feeling after a cursory tour of the property.

"The best way to help private renters is to ensure they have the information to know what they are getting into."

Consumer Focus said it would also like to see a quality mark introduced for all private landlord accreditation projects.

There are at least 80 different types of voluntary landlord schemes in England, it added, with a wide variation in standards required to belong to them.