Nowhere does the profile state explicitly that if you are an attractive female traveler, you might skip the couch entirely and wind up in Riccardo’s bed, but it’s a good possibility.In eight months using the service, Riccardo, who is 32 and works for an ad agency, has let eight visitors crash at his apartment, of whom he’s hooked up with five, for a 62 percent “success rate.” If you count the additional two who climbed into bed with him for a cuddle and then fell asleep, the percentage climbs even higher.

(Riccardo and other Couchsurfing users quoted in this article asked to be identified by pseudonyms.) On the business front, the crowdsourced hospitality site has been experiencing a rough patch lately.

After a controversial transition to a for-profit model in 2011, which brought $22 million in funding in the past two years, growing pains have set in.

“My first Couchsurfing hookup happened when I was staying with my friend in Miami,” Riccardo recalls. Months later Riccardo got a phone call from the same girl, asking if she could stay at his place in New York City. “I never talked to her again,” he admits, adding, “I mean, we’re friends on Facebook.” Couchsurfing was born after a budget-conscious traveler named Casey Fenton sent out a mass request for accommodations in Iceland and received 50 invitations from students with a free spare futon.

“He has a studio and was hosting two girls from France.” He slept on an inflatable air mattress with one girl, while his friend shared his bed with the other. Fenton soon realized people all over the world might not mind sharing their extra space gratis while making new friends in the process.

Members can request a couch, host a traveler, or find new friends to meet up with locally.

Riccardo agrees to host only female travelers and stipulates that they be younger than him.

Today, each of the site’s 7 million members has a unique profile which reads like a personal ad, highlighting interests, locations traveled, details about their accommodations and, most important, references.

This system allows friends you’ve made globally or locally to vouch for you and the unlikelihood of you being a serial killer.

His friend later advised him on a more direct strategy.