Over the course of 2009 there was an increase of +15% in cases of overcrowding, according to Landlord Action, with more cases in London than the rest of the UK, which it believes is a direct result of the recession.

Paul Shamplina, Landlord Action’s director, said: “The most common cases appear to be organised gangs looking for an easy money making scam. They take out a tenancy and then sublet to multiple occupants. The worst case we have dealt with was a three-bedroom, one bathroom, semi-detached house in North London which was found to have had 53 occupants, all illegal immigrants. There were mattresses literally littering the floors from wall to wall in every available space. The sanitation issues were stretched to say the least.

“Another case was of a lady who had a lovely two bedroom flat in Victoria. Her tenant paid six months up front but she later discovered that 18 sets of bunk beds had been put into her property and it was being used as a youth hostel. A website in China was offering students visiting London accommodation at £20 per night.”

Shamplina recommends that landlords ensure they have a good relationship with neighbours and caretakers so they can be apprised of any such behaviour. With most cases being reported by vigilant observers having complained about noise levels, or the property falling into disrepair due to excess occupants. The local police generally are not inclined to get involved, often classing it as a civil matter.

Shamplina said: “If a landlord suspects subletting is happening in the property, whilst I would advise that the sub tenants are spoken to directly to clarify the situation as they may well be unaware of the circumstances themselves, a landlord should never accept payment direct from this source as this would be seen to be giving them authority to be in residence. I would suggest that, if they are happy for them to remain, they cut out the middle man by going through the proper procedures to have the tenancy negated, then draw up a new tenancy for each resident. Under no circumstances should they accept payment of rent until the matter is sorted.”