Today, the apartment bears little resemblance to its former self. With the eventual blessing of his benevolent landlords, Grattan has completely transformed the rental unit— widening doorways, upgrading electrical systems, and reimagining every wall and ceiling. (Think leopard print in the den and kelly green in the central dressing area.) He gutted the kitchen, replacing an outdated scheme with a sexy mélange of mirror, lacquer, Rouge Griotte marble, and African mahogany. All that remains of the old bathroom is the tub, now refinished in a cherry hue and complemented by a blue-glass shower panel, red mosaic tile, and a matte-black toilet and fittings.

“It was all trial and error,” says Grattan, a virtuosic cabinetmaker and jack-of-all-trades who spent months living in a construction site, executing the renovation alongside the similarly intrepid Lynx Contracting. “If you haven’t negotiated with reality you haven’t designed, you’ve fantasized,” he avers. “If you can’t build it, you don’t fully understand it.”