They met in Venice, dated in Kenya, married in New York, and eventually settled into an 887-square-foot Brooklyn walk-up. After calling the world home for years, Italian Davide Cernuschi and American Renay Arbour had to figure out how to squeeze their sprawling sensibilities into digs much smaller than an Alitalia airplane. "We use every inch," says Arbour. Doing so called for creativity and compromise, two skills the couple has a knack for: He's a photographer for such magazines as Rolling Stone; she's a J.Crew fit model. Architect Carlo Formisano helped the jet-setters execute bold moves like tearing out walls to let in light and turning an often-ignored feature, the staircase, into a striking room divider. Since the sun provides ample brightness, the former international travelers chose neutral-hued furniture with clean lines. "It's so perfect and balanced," says Cernuschi. "We don't have to go out."