Consumer watchdog Which? has turned its focus to the lettings sector, urging tenants to share horror stories of so-called agent mistreatment.

It has formulated a hashtag on twitter, #RentRage, that encourages tenants to reveal their experiences of letting agents.

It comes as Which? urged letting agents to get their house in order after an investigation found many failed to follow industry practice on health and safety information.

Which? sent undercover researchers on 30 property viewings across England and Scotland to assess the conditions of properties and also provided them with a list of questions to ask the letting agent, designed to uncover whether they were giving vital information and following health and safety rules.

Viewings took place in Bristol, Edinburgh, Leeds, London and Manchester, and scores were provided based on what property commentator Kate Faulkner and Which? felt best practice should be.

Half of agents were unable to provide any information at all on the property’s boiler and only 13% were able to supply the correct details about annual servicing rules, according to the mystery shopping exercise.

Meanwhile, just one in three agents were rated ‘good’ for their knowledge of carbon monoxide alarms, meaning they were able to explain they were required, where they were in the property and if they had been tested.

Agents performed better on knowing about the importance of and where the smoke alarms were in the property, with 21 out of the 30 rated ‘good’ on this measure and two rated ‘bad’.

Additionally, the researchers found that 20% of the properties visited had problems with damp, with none of the agents able to commit to fixing the problem.

Eight out of 30 viewings were rated ‘poor’ for answers to questions on property maintenance and repairs.

Investigators said lettings agents brushed off questions about maintenance, instead stating that work would be carried out before the tenant moved in, or would need to be dealt with by the landlord. Faulkner said required repairs should be made conditional as a special clause in the tenancy agreement rather than being agreed verbally.

Agents were also criticised for their explanation of holding deposits. Firms allegedly struggled to explain how much these payments would be and how they would be refunded.

Which? said fees for security deposits and administration were explained better, but warned these ranged from £20 to £400.

Alex Neill, managing director of home products and services for Which? said: “There are clearly real issues with letting agents showing prospective tenants properties that aren’t up to scratch. It’s unacceptable that all too often agents can’t answer basic questions about important issues like boiler safety and carbon monoxide alarms.

​”Tenants need ​to be ​given clear and accurate information before moving in to a new place​ and agents must do more to deliver an acceptable level of service​.”