You'd think the first rule of buying in the Urban Glass House — the Spring Street development that is both the late Philip Johnson's final project and an homage to his iconic New Canaan, Connecticut, home — would be to never, ever throw stones. But, several purchasers argue, the developer's tardiness is making that impossible. "They said it would be ready in July, but we're still waiting," says the disgruntled buyer of one of the building's 40 units, with prices that average $1,600 per square foot. Developer Scott Sabbagh, who bought the site two years ago after a 300-foot, Johnson-designed tower planned for it was nixed by preservationist groups, says the delays were unfortunate but worth it. "When you're doing things that are not commonly done, construction takes longer," he says, noting the high-end finishes by Annabelle Selldorf, who designed the Abercrombie & Fitch flagship on Fifth Avenue, and complications like having to reinforce the neighboring Ear Inn, which risked collapsing. Sabbagh says condos started closing on November 10, but that stone-throwing buyer is still living in temporary housing and says he hasn't yet heard about a move-in date. "They don't call with updates," he says. "It's not nice." —Deborah Schoeneman