Phia’s Phoebe Gates with 37 East 18th Street (Getty, LinkedIn, Google Maps)Phoebe Gates’ fast-growing AI shopping startup has found a new home in the Flatiron District. Phia, the AI-powered price comparison platform founded by Microsoft co-founder Bill Gates’ youngest daughter and her Stanford classmate Sophia Kianni, signed a lease for the 8,900-square-foot penthouse at 37 East 18th Street, The Real Deal has learned. The length of the lease and asking rent at the newly redeveloped office buildi