Estate agents offer illegal 'beds in sheds'
High street estate agents are renting out so-called "beds in sheds" without residential planning permission, a BBC investigation has found.
Inside Out caught two companies - Hunters and Milestone - offering sub-standard housing on behalf of landlords.
Receipts show Milestone, in Willesden Green, had let a garage without windows to a young family.
The firm claims to have nothing to do with the property.
When London councils began investigating this issue, it was common to see squalid shacks in back gardens, typically inhabited by numerous illegal immigrants.
A survey carried out by Brent Council turned up hundreds of outhouses built in this way.
Often the owners claim the buildings are more than four years old, because they are then immune from planning enforcement.
Milestone were charging young father Andreas Luiz £1,000 a month to house his wife and child in a small, windowless room with a fake garage door.
After Inside Out began inquiring about the property, Mr Luiz, a construction worker, said: "The agency came and they asked me not to show the contracts or the receipts to the BBC.
"I told them I already had."
The lettings agency repeatedly refused to answer the BBC's questions. When a reporter turned up unannounced the sales team denied the property was even on their books.
A member of staff at Milestone said: "It's not on our system and I don't understand what you are talking about, so I'm asking you to leave."
But the BBC has seen receipts from the firm showing more than £2,000 had been taken in rent and deposits on behalf of the landlord.
'Bright and airy'
Meanwhile the BBC saw another garage conversion with no planning permission in Wembley advertised by Hunters estate agents in Harrow.
The advert described it as "stunning, newly refurbished, bright and airy".
A spokesman for the estate agents said: "The employee who handled the letting is no longer employed by us but it is certainly not company policy to let a property that does not have planning permission.
"We acted in good faith and are most concerned in retrospect that we were not aware of the full facts in this case."
Property Ombudsman Christopher Hamer said: "A letting agent is the professional in the transaction.
"It's the agent's responsibility to make further inquiries to be more diligent in understanding the status of that property before they describe it to prospective tenants.
"Based on their experience, if they see something that's not right in terms of the residential status of that property, they need to be more diligent than normal."
But these cases are far from isolated.
Newham, Southwark and Ealing councils also described estate agents marketing garages and sheds that fail to meet the most basic legal requirements for habitation, such as windows.
Muhammed Butt, leader of Brent Council, admitted: "There are probably hundreds more properties we are missing.
"All these estate agents who are advertising these type of properties will be contacted by our enforcement teams as well."
BBC Inside Out is on BBC One in the London region on Monday, 25 February at 19:30 GMT and nationwide on the iPlayer for seven days following transmission.