Scene in Berlin

I though it was a joke when I first heard that a jobless friend of a friend had rented a tent on the sandy beaches at Tropical Islands - an amusement park just outside of Berlin - in order to sublet his flat for the entire winter. But it was true: The guy is still living there and enjoying the artificial balmy climate rather than the dreary Berlin drizzle - for only 59 euros ($76) a month. Meanwhile, his apartment is available for paying tourists who cover not just his rent, but also enough extra to make unemployment a comfortable lifestyle.

I still have a job, but I'll definitely keep this idea in mind for the day I get fed up with the Berlin winter.

It seems to be a global trend for people to sublet their apartments to tourists who'd rather not pay hotel prices. But in Berlin, this kind of business is becoming an alternative way of living.

The 'Mr. Right' apartment

There are numerous online platforms where people can advertise and rent out flats on a daily, weekly or monthly basis. "More value for your money," "More privacy," "Get to know the local lifestyle" - slogans like these attract millions of tourists to Berlin apartments.

They pay less and the tenant is happy to earn some extra money, often under the table. A win-win situation, plus home-made coffee, fresh bread from the local bakery and a washing machine.

That is, as long as the landlord doesn't know anything about it. And usually he doesn't, in a city where people move in and out like mad, constantly adjusting their apartment to their ever-changing lifestyle - smaller, bigger, cheaper, more luxurious. In Berlin, finding the perfect apartment is like finding the perfect partner: It can take years. And until then, you have to settle for short-term solutions.

Collateral damage

According to the Berlin Hotel Association (DEHOGA), there are between 15,000 and 25,000 holiday apartments in the city. But only 31 businesses, incorporating 2,729 beds, are legally registered.

Where, I wonder, are the other 10,000 odd Berliners are living? Probably at friends' places.

I should know better. I used to host a friend every now and then for a few weeks; she had lost her job and desperately needed to sublet her flat in downtown Berlin. She quickly created an ad with pictures for one of the many online platforms.

A piece of cake. The offers kept coming and, with the rental price of a few days, my friend could finance the rent for the whole month. Her two-bedroom flat with a balcony could house a whole family for 90-100 euros a day, so just over a week of subletting covered her monthly bill.

"There appears to be no rule against holiday renting in Berlin," I just read on 9fkats.com, one of the most popular flat rental websites at the moment.

There may be a bit a grey area between the lines, but if you want to stay on the legal side, you definitely have to ask your landlord for permission and register your business with the local tax authorities. Berliners, it seems, are much more willing to share with tourists than with the state.

Keeping everyone happy

Especially if they want to finance their own holidays this way. A good friend of mine moved to Berlin a few years ago and, as he says, often couldn't make ends meet. So when returned to the UK for a week or so, he would rent out his room.

"My rent was 250 euros a month," he told me, "and I would charge that much for a whole week. Everyone was happy." Most of his visitors fit into the 18-to-30-year-old backpacker category, from the US or other European countries.

Literally tens of thousands of Berliners are doing the same - to the dissatisfaction of some hotel owners who have started complaining about unfair competition. As Europe's third popular tourist destination after London and Paris, Berlin attracts about 10 million visitors a year, so I don't think the hotel industry is significantly endangered by the clandestine subletters.

Living in the holiday

Another trendy - and legal - way to make use of your home and save money for travel is the house exchange concept, like in the movie "The Holiday:" The character played by Kate Winslet exchanges her cottage near London for a luxury mansion in L.A. belonging to a movie trailer producer played by Cameron Diaz.

"Simply post information about your house swap offer including your preferred destination and dates. Once a match is made, it's up to you and your exchange partner to work out the details," according to homeexchangeplace.com. Members pay a yearly membership fee and can choose from thousands of homes all over the world - if they can find a match with someone who wants to stay in their place. But you could get lucky, like Winslet's character or a friend of mine, who once exchanged her flat in Berlin for a villa with pool in Mexico.

The trick, of course, is to live in a place where others go on holiday. Your cramped one-bedroom in exciting Berlin might be worth beach-front property in the Caribbean or, if not, at least an artificial blue lagoon for 59 euros a month. Basically all you need is Berlin and one of its many roofs above your head.