The wife of India’s richest man, Nita Ambani has built a model township, an elite school, and a Premier League cricket team. But all anyone wants to talk about is her house: the 27-story, 570-foot-tall, 400,000-square-foot Xanadu that few have entered but that has all Mumbai buzzing. Discussing her home for the first time, Nita Ambani talks with James Reginato.