The housing market is the least affordable it’s been since 1984, and the baby boomer generation, which struggled to get off its feet in the ’80s, has the cash and the equity today to muscle millennials out. In fact, recent data shows the median age of a U.S. homeowner is 59 years old. Enter “carpooling for homes.”

Austin Allison, cofounder and CEO of property brokerage Pacaso, sees the growing trend of co-ownership as a kind of life hack, the way you would with a commute.

“Co-ownership is like carpooling for homes,” he tells Fortune. “Co-owning with family or friends offers a solution, lowering the entry barrier and addressing affordability challenges.”

Opendoor Technologies, an online company that buys and sells residential real estate, found first-time homeownership in co-buying is becoming more common among first-time homebuyers, particularly millennials. Jennifer Patchen, an Opendoor real estate broker, says this should come as no surprise, given it’s millennials who introduced crowdfunding and are also notorious for wanting to generate passive income and work side hustles.

“Millennials are often the ones looking for alternative strategies for funding a home and are really leading the charge for redefining traditional homeownership,” Patchen tells Fortune. “The primary drive of co-ownership is cost saving. Co-buying allows millennials to buy now, securing an affordable place to live in the present, while setting up a solid investment for the future.”