On 26 November 2014, the BBC's Hugh Schofield in the BBC News on-line wrote about the Airbnb 'internet phenomenon' which enables people to find short term accommodation cheaper to rent than a room in an hotel. As he said in his article: '... a boon for tourists ... But in some cities the explosion of holiday lets is beginning to cause serious concern.'

He went on to explore the impact this is having on one city - Paris. Within the context of issues with another phenomenon - the housing market in the UK, HMOs and rise of the private rented sector- it is interesting at least to look at some of the parallels. ...

'The authorities in Paris are so worried about the drain on residential property that they have enacted drastic measures to bring it under control.

However, so far few property owners have complied with the new rules.

Under French law you can rent out your flat for short periods to holiday-makers - as long as it is your primary residence.

But City Hall in Paris believes that as many as two-thirds of properties being rented on very short lets are not primary residences.

They are flats that are being used solely for making money via year-round holiday lets, the authorities say. And in the vast majority of cases their owners are flouting the law.

Some Parisians worry that holiday lets are changing the character of neighbourhoods

As a result it is estimated that a staggering 20,000 people - foreigners as well as French - are today liable for fines of thousands of euros.

Very short term internet flat rentals have seen a vertiginous increase in the last three or four years, in Paris as well as in cities like New York and Barcelona.

The last study, carried out in 2011, put the number of Paris apartments being let out to tourists at 20,000. Today officials say it has risen to 30,000.

"Holiday lets are an extremely profitable business," explains Francois Plottin, who runs a team of 20 inspectors at City Hall.

"A small flat can make in a week what it would normally make in a month if it was let out to locals."

"And because of the popularity of Paris as a tourist destination, the occupancy rate is very high. Flats are typically let out for 75 or 80% of the year."

But French law says that the minimum period for letting out a residential property is one year.

To let out a flat for shorter periods requires registering it as a commercial property. And - despite repeated warnings - that is something that only a tiny fraction of owners have bothered to do.

At Airbnb - by far the biggest internet site dealing in holiday lets - they say that the vast majority of their business is with people legally letting primary residences.

The figure offered by Airbnb's Paris director Nicolas Ferrary is 83%. However, that is disputed by Francois Plottin, who says around half of properties advertised on Airbnb are not primary residences.

"We do everything to comply with the rules, and it is clearly signposted to users of our website what those rules are," says Mr Ferrary.'