The sharing economy has taken the main stage, challenging traditional models of just about everything. While it’s uncontested that consumers benefit from home-sharing services like Airbnb and car rental apps like Turo, just how lucrative is it for people actually renting out their apartments and cars?

It depends on where you live, of course.

ShareaCamper, a peer-to-peer rental platform for RVs across Germany, Australia and New Zealand, created a 2017 Return on Investment Index to uncover where the sharing economy pays off the most. The study analyzed 31 cities across European, North American and Australian markets to determine which cities provide the highest returns on asset investment across five categories — homes, cars, boats, RVs and money lending.

Where in the world does it pay off?

Barcelona, Spain takes first place, with ShareaCamper ranking it the best city to pay off an investment across all five categories.

As one of the most visited destinations in Europe — and the world — the Spanish city experienced a 5.7% increase in tourists between 2014 and 2015. Barcelona’s government, like many others around the world, hasn’t been as accepting of the sharing economy. The mayor of Barcelona fined Airbnb and HomeAway 600,000 euros each for listing unlicensed apartments.

Meanwhile, Frankfurt, Germany is the best place to buy a home and pay it off using services like Airbnb or HomeAway. With a 13.48% yearly rate of return, it takes people seven years, on average, to recoup the initial investment in the home.

The cities with the highest ROI for a car and boat, respectively, are Zurich, Switzerland and Melbourne, Australia.

Here are the top 10 cities overall —

1. Barcelona, Spain

2. Wellington, New Zealand

3. Melbourne, Australia

4. Sydney, Australia

5. Auckland, New Zealand

6. Copenhagen, Denmark,

7. Madrid, Spain

8. Hamburg, Germany

9. Geneva, Switzerland

10. Dublin, Ireland

It’s notable that no US cities made the top rankings for highest ROI. The highest ranked US cities are Miami (14th), Los Angeles (18) and New York (23).

Cities were ranked by the total time needed to recoup the initial investment, based on the return of investment percentage for 1,000 assets per city.

ShareaCamper used the asset-specific occupancy rates, rental prices and original retail price in addition to any taxes and usage fees paid to the peer-to-peer platform to calculate the time that it would take to pay off the asset itself. The company plans to extend the research to all continents in the future.

ShareaCamper used data from rental platforms like Homeaway, Airbnb, Drivy, Boathound, ShareaCamper and Prosper. The company did not include Uber in calculations for car sharing because many drivers use the platform as their full-time employment.