Why did a coliving startup just acquire a Craigslist alternative?

For the data.

Common, a startup that is building a network of community-minded, flexible housing (also known as “coliving”), acquired Skylight, a marketplace for subleases, so that it could better understand the informal, short-term real estate market.

Because Common rents rooms rather than entire apartments, typical real estate data doesn’t perfectly apply. “There’s no data on what roommates want,” says Brad Hargreaves, the founder and CEO of Common. “All of the data is about one bedrooms, two bedrooms, and studios.”

Its product is more comparable to a sublease in an apartment with roommates, like many of the ones offered on Craigslist. In both cases, renters typically share common space, don’t have to buy kitchen supplies, and don’t pay a broker fee—all of which could factor into the appropriate price. Skylight has about 125,000 users, about 3% of whom have listed subleases on the site (most are shopping for leases), and their behavior will help Common make decisions about how to price rooms and what amenities to offer.

Common, which in October opened its first building in Brooklyn, has since expanded to four buildings, including one in San Francisco. It plans to add four more by the end of the year—in neighborhoods partially based on data from Skylight.SK