Eventually, they came across a two-acre plot near Karjat, a city 40 miles from Mumbai, that was surrounded by the grassy peaks of the Western Ghats mountain range. “It was just beautiful. It was exactly the backdrop that we wanted,” Mr. Shah said. They bought the lot for 6 million Indian rupees, or $67,000, nearly a decade ago, and decided to build a farmstead there to grow mangoes and other crops.