Inside the Miami penthouse of Carmen Busquets, queen of ecommerce

Let’s say you’re a wildly successful entrepreneur, investor and philanthropist who craves all-white interiors, dramatically open spaces and beach sunsets fit for a postcard. Where do you buy your slice of paradise? One obvious option is Florida’s Key Biscayne, the exclusive island retreat just south of Miami Beach. And if you’re Carmen Busquets, the so-called fairy godmother of fashion ecommerce, you buy a sprawling beachfront penthouse where the storied Sonesta Beach Resort once…