The Covid-19 pandemic has achieved what many mayors across Europe have tried and failed to do.
It has wiped out tens of thousands of Airbnbs from city centres and so help lower rental costs for locals, in some places by as much as 15%.
While Europe's cities have long welcomed tourists, critics say the surge of properties listed on short-lettings site Airbnb in recent years had priced many locals out of their own housing markets.
Reuters talked to property management companies and landlords in cities including Lisbon, Barcelona, Prague, and Venice.
They said the collapse of tourism in the pandemic meant some hosts had now replaced holidaymakers with mid to long-term tenants, moved in themselves, or given up properties altogether.
Data from holiday rental analytics firm AirDNA showed the number of Airbnb listings with at least one night booked or available in the past month in Europe's 50 largest cities plunged 21.9% year-on-year in 2020.
Airbnb says it has adapted to changing travel patterns, with people heading to smaller towns and cities rather than tourist hotspots.
"We had more listings in France, Germany, Portugal, Spain and the Czech Republic combined at the end of 2020 than the end of 2019," spokesperson Andreu Castellano told Reuters.
While some hosts in major European city destinations plan to return to Airbnb when tourists come back, others have left the holiday-let business for good.
"If tourism had come back faster, maybe I wouldn't have taken this decision. But I can't go another year without a clear sense of when money is coming in," said Vanessa Rola.
She had been renting four apartments in Lisbon's Graça district on travel platforms including Airbnb.
Without tourists, she could not pay her own rent, and is in the process of ending her contracts.
In Venice, where AirDNA data showed year-on-year bookings for Airbnb and rival Vrbo combined were down 67% in January, residents' activists are urging the government to seize the opportunity to help locals by, for example, capping rental days and converting empty space into low-cost housing.
"Before the pandemic, renting in Venice had become almost impossible for normal people," Marco Gasparinetti from residents' rights group Gruppo 25 Aprile told Reuters, blaming short-term lets for pushing up prices. The city of just 60,000 residents is normally visited by 20 million tourists a year.
"There are 30,000 people who commute to Venice every day but can't afford to live here. Now that could change and help make sure Venice is not just an open-air theme park for tourists," he added.
Last month, Airbnb reported better-than-expected bookings in its first earnings release since going public, buoyed by countryside getaways and a rebound in demand in North America.
Business was weakest in Europe, the Middle East and Africa amid Covid-19 lockdowns and travel curbs.
For years, European mayors have struggled to rein in the proliferation of vacation properties in city centres, lacking the data to enforce limits on rental days or the number of properties in a building used for holiday lets.
Airbnb, Expedia, Tripadvisor and Booking.com agreed last March to share data with the European Union's statistics agency on the number of nights and guests booked, and 2020 figures are expected in the second half of this year, Eurostat said.
Last September, 22 mayors wrote to EU competition chief Margrethe Vestager urging her to extend data-sharing to city administrations, so they could "secure the liveability of our neighbourhoods."
"As tourism returns, we must make it sustainable - creating a model that isn't prohibitive to holiday lets but does have limits which ensure this is a city you can visit, but also where you can live and work," Ricardo Valente, a councillor in Porto - one of the signatory cities - told Reuters.
But Covid-19 lockdowns and restrictions on cross-border travel are doing the job for some city authorities – at least for now.
In Lisbon, which saw huge growth in Airbnbs in the historic centre, around 5,000 of the city's roughly 25,000 listings have disappeared from the website during the pandemic, according to website Inside Airbnb.
Rental prices fell by 15% between March and December 2020, according to real estate database Confidencial Imobiliario, attributed largely to the sudden availability of thousands of former holiday lets.
In Prague, Airbnb listings tumbled from just over 14,500 to less than 8,000, according to Inside Airbnb.
Rents have fallen by around 8%, real estate developer Trigema reported.
Airbnb, however, says it has proved resilient amid shifting demand. "Guests are getting out of city centres and booking whole homes," Castellano said. "The Airbnb platform inherently adapts to where demand is ... we adapt to guests' needs."
But not everyone in city centres is giving up.
Data from Portugal shows that while thousands of properties have fallen off Airbnb, just 114 have given up their holiday-let licence - a coveted asset in the city's historic districts, where the local council prohibited new licences from being issued in 2019.
Programmes attempting to lure Airbnb owners onto the social housing market through tax incentives and the promise of a five-year contract have so far seen slow uptake: just 34 properties in Lisbon and 12 in Porto, the city councils said.
Instead, some landlords are using local letting websites or their own direct booking channels to find longer-term tenants.
Airbnb released three videos last month entitled "Made Possible By Hosts", widely seen as an attempt to woo back those who had left the platform.
But for some, the wait is unaffordable.
AirDNA data showed forward bookings in Rome, Lisbon and Budapest were 85-90% below last year's levels at the end of March.
By contrast, bookings across US holiday rental platforms were just 2% below last year, their data showed.
Eduardo Miranda, head of Portugal's holiday let association, expects around 15% of Airbnbs to stay off the market in Lisbon for good, even when tourism returns.
"This is going to be another year of sacrifice," Miranda said. "The best of this summer will be lost. And if the summer is lost, the year is lost. Those who stay in the business will be the ones who really care," he added.