Purpose-built rental housing is expected to see its most prolific year ever, with nearly 14,000 new units set to open in 2022, according to a recent study by RentCafe. That'll surpass last year's record-breaking delivery of 6,740 new build-to-rent homes. Keaton Merrell, managing director of capital markets at commercial real estate financial-services firm Walker & Dunlop, said an estimated 500,000 starts are expected in the next five years within the build-to-rent sector.