It took David and Mayuko Lai five years to find a buildable lot in Los Angeles. That’s a drop in the bucket, however, compared to how long they plan to stay put. After visiting too many overpriced, impossibly steep sites, the Lais finally found a flat lot in Culver City. Harboring a dilapidated 1950s home, the property was listed as a place to "build your own dream house," and that’s just what the couple did. Along with Cara Lee and Stephan Mundwiler of Lee + Mundwiler Architects, they devised a design with solar panels; a tankless water heater; a cool roof; and room for their three kids, Maya, Yumi, and Shota. In constructing their ideal abode, David and Mayuko created a new family heirloom: a house in which to live out their days, then pass on to the next generations.