New York state passed a bill aimed at protecting lower-income families from skyrocketing rents

Berlin has become the latest anti-gentrification battleground, with authorities poised Tuesday to freeze rents for five years in a bid to halt skyrocketing costs.

Other capitals have taken different approaches. Here is an overview of some of them.

New York

Lawmakers in New York state last Friday (June 14) passed a bill aimed at protecting lower-income families from skyrocketing rents.

The new law eliminates rules that allowed building owners to increase the rent when an apartment changed hands.

It will also prevent new tenants from being charged for extensive renovations via increased rents, and help keep owners from reducing the number of rent-controlled apartments.

Since 1994, about 300,000 rent-controlled apartments have vanished in the city of New York alone, according to official figures.

That has forced low-income and even middle-class families to move, fuelling gentrification of the Big Apple, one of the world's top 10 most expensive cities.

The new law should directly affect about 2.4 million New Yorkers, out of a population of roughly 8.5 million, who live in close to one million rent-controlled apartments.

Vienna

The Austrian city boasts the title of the "capital with the most affordable housing" thanks to its large social property stock.

Among its 1.9 million inhabitants, six in 10 live in apartments owned by the city or by non-profit developers -- something that helps brake rent rises.

The city keeps the qualifying cap for social housing high -- 3,317 euros ($3,728) on a 14-month basis for an individual and 6,245 euros for a family of four, meaning such property remains within reach for middle-class families.

As such apartments can be passed on to family members, critics say the cap fails to take into account changes in revenues or family structures.

Barcelona

Rentals have shot up by 35 percent since 2010 partly due to the proliferation of the lucrative holiday let apartments driven by Airbnb in the Spanish seaside city.

In a bid to curb runaway rates, the city has forced thousands of short-let apartment owners without tourist licences to halt their businesses. It has also stopped issuing new licences for such short-term lets.

The authorities have also hired people to comb through Airbnb ads to identify those who fall foul of the law.

Paris

The French capital will start applying a rent cap from July 1, bringing back a measure that had already been deployed between 2015 and 2017.

The limit comes on top of another measure in place for several years that restricts sharp rent hikes when apartments change hands between tenants.

In a bid to ward off pressure put on housing by Airbnb, the city is also seeking to ban such short-term lets in the city centre.

Stockholm

Rentals in the Swedish capital are tightly regulated, with 44 percent let out by institutions or private individuals.

Their rates are determined annually, jointly by property owners and tenants association.

To obtain one of these apartments, those interested have to join a queue with a waiting list of as long as 20 years, or win a draw much like a lottery.

A holder of such a lease can keep it for life and even exchange it for another apartment. But conditions for subletting are limited to military service or a foreign posting.

Other apartments are let by individual property owners, but only with the agreement of other owners in the building. Leases are however often short and non-transferable.

The tightly regulated market has given rise to a black market where would-be tenants desperate to find an apartment either buy a lease with a cash top-up, or sublet without the necessary permission.

In 2017, a government report found that one in four leases were obtained fraudulently.