Despite what most people imagine, you don't just find 3,300-square-foot apartments in Berlin these days — they have to find you. In Judith Seng and Alex Valder's case, it was a newly divorced friend of a friend, abandoning the loft he'd lived and worked in with his musician wife, and searching for someone who could fill the sprawling space. Seng and Valder, two process-oriented product designers with a habit of accumulating furniture off the street, signed the lease immediately. In May, they moved their home from a 1960s Socialist housing bloc on the historic GDR boulevard Karl-Marx-Allee, then packed up their separate studios, creating a common office in the apartment's living area. There's a dishwasher and a fancy Duravit bathtub, a spare bedroom and a roof terrace. Space may be abundant and cheap in Berlin, but this is not the norm. Friends seeing it for the first time routinely gape.