The Summerdale apartments used to look a lot like many other housing complexes in low-income parts of US cities. It’s a compound of low-slung suburban-style buildings built in two phases starting in the early 1970s, located near Interstate 75 in Atlanta’s Glenrose Heights neighborhood

When developer Marjy Stagmeier’s firm, TriStar Realty, bought the 244-unit property in 2018, Summerdale needed millions of dollars in repairs. Tenants reported mold and insect infestations, broken appliances and leaking roofs; several units were vacant and partially burned out. The conditions took a particularly harsh toll on Summerdale’s youngest residents: Of the 68 children living there who attended nearby Cleveland Avenue Elementary School, most had asthma, Stagmeier says.