New apartments and condominiums are opening on San Francisco’s Treasure Island and Yerba Buena Island, a 576-acre former U.S. Navy site abandoned in 1997. Eight buildings contain about 1,000 homes, while developers plan another 7,000 units for an eventual population of about 18,000. More than 300 acres are reserved for parks and open space, but the full plan may not be completed until at least 2040. The project took more than 25 years to produce its first homes because of lawsuits, public opposition, extensive infrastructure requirements and disputes over affordability and density. Residents include buyers paying as much as $3.2 million, renters seeking lower housing costs, and formerly homeless and veteran residents in subsidized housing. Supporters call the redevelopment a success in a housing-constrained city, while critics say its planned density is far below what the islands could support. Traffic, parking, sea-level rise, earthquake safety and San Francisco’s costly building requirements remain additional challenges.