Default talk alarms Riverton’s residents 

As the residents of the Riverton complex in Harlem wait for news on whether the building’s owners will default on their $225 million mortgage, observers wonder if it will be the first casualty among many rent-regulated properties bought by private equity firms. About 90 percent of the complex’s 1,232 apartments are rent-regulated, and residents worry that the building’s maintenance will suffer while its fate is decided. Laurence Gluck of Stellar Management and the Rockpoint Group, an equity firm, bought it three years ago. Residents of the complex at 135th and 138th streets and Fifth Avenue have included jazz pianist Billy Taylor and former Mayor David Dinkins.