Seeing the opportunity and high demand, institutional investors are snatching up as much U.S. real estate as they can. Investors purchased 18.4% of homes in the fourth quarter—a record high, according to housing data from Redfin.

Investors are seeing opportunities in turning homes into rentals and commanding higher rents or have plans to flip homes to take advantage of rising prices. Investors were defined in the study as any institution or business that purchases residential real estate.

Investors are snatching up the highest amount of properties in Atlanta, Charlotte, N.C., and Jacksonville, Fla.

Investors purchased 80,293 homes in the fourth quarter, up nearly 44% from a year earlier, according to Redfin’s data. Limited housing inventories are constraining investors from purchasing even more.

Invitation Homes CEO Dallas Tanner told CNBC that after buying 1,500 homes in the last quarter, “we wish we could buy more. Demand is so large.” Tanner says the housing supply is tight. He says the properties they’re buying they plan to hold onto over the long haul within their ever-expanding portfolio of properties.

“While record-high home prices are problematic for individual home buyers, they’re one reason why investor demand is stronger than ever,” says Sheharyar Bokhari, Redfin economist, about the study’s findings. “Investors are chasing rising prices because rental payments are also skyrocketing, incentivizing investors who plan to rent out the homes they buy. The supply shortage is also an advantage for landlords, as many people who can’t find a home to buy are forced to rent instead. Plus, investors who ‘flip’ homes see potential to turn a big profit as home prices soar.”