The living room palette complements the azul waters outside—from the owners’ vintage rug and marble coffee table (with a new base conceived by Brown and Davis) to a custom sofa also by the designers in a pale gray crushed velvet by Pierre Frey, flanked by vintage drum tables from Craig Van Den Brulle. The Steinway & Sons piano, a family heirloom, was relacquered in a high-gloss black.