When Tenants Can’t Be Evicted

Two years ago, while walking his family’s new puppy, Paul Boardman had the kind of epiphany only a real estate entrepreneur can have.

A developer who was once the lead designer for all the Equinox gyms, Mr. Boardman was passing by 711 West End Avenue in Manhattan, a seven-story apartment building of red brick and squat windows between 94th and 95th streets that looked almost as if it were shrinking from the grand prewar buildings around it that are twice its size.