In just three years, Airbnb, the apartment-sharing startup, has gone from a Y Combinator startup to a company worth at least $1 billion to venture capitalists.

The company announced this morning it had pulled in a huge funding round of $112 million led by VC firm Andreessen Horowitz to expand abroad. DST Capital and General Catalyst Partners also joined the funding.

Airbnb allows people to rent out their apartments or houses to those looking for out-of-the-ordinary travel experiences. Some have likened it to the eBay of travel.

The Wall Street Journal reports this funding round, meant to boost Airbnb’s Internet-enabled service abroad, is about 14 times the $7 million the company had previously raised. It comes just three years after Airbnb got its first boost by enrolling in the Y Combinator incubator in San Francisco. The Financial Times places the value of Airbnb at $1.3 billion as a result of the funding.

CEO Brian Chesky and partners Joe Gebbia and Nathan Blecharczyk, all in their twenties, started Airbnb in 2007 to raise rent money by renting their own San Francisco apartment.

The funding round has been expected for some time, as Portfolio.com reported in June.

And it comes at a time when venture capitalists are particularly bullish on Internet startups like Airbnb. VCs poured more money into Internet companies in the second quarter than at any time in a decade, a recent report for the National Venture Capital Association showed.

As with other $1 billion-plus valued startups—think Groupon and Twitter—Airbnb has been marked by impressive growth, but also problems.

Romy Ribitzky wrote in Portfolio.com in June that Airbnb was accused of “farming Craigslist,” to boost its number of listings.

The company responded at that time:

"We did have remote salespeople that we contracted to acquire listings through person-to-person sales, but their efforts were largely ineffective.

We have since learned that some of these remote contract salespeople were apparently aggressive with their outreach and may have used Craigslist to attract customers to our service who were not open to solicitation. This is not a tactic we condone or endorse, and it is our policy to forbid such actions."

The official announcement of funding this morning, though, was all about the upside of Airbnb.

“The Airbnb movement has changed the way people experience the world,” said Gebbia, the company's cofounder and chief product officer. “This investment will help us respond to increasing international demand by accelerating hiring, and the opening of offices around the world, in order to support our growing community on more local levels.”

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Kent Bernhard Jr. is News Editor of Portfolio.com