Billionaires are increasing multi-million buck homes on mega-ranches. Sales agent Robb Nelson says it’s a valid estate “Bonanza.” Old New York City Mayor Michael Bloomberg paid $46 million for a 4,600-acre ranch in Colorado. A 41,000-acre ranch in South Dakota goes for $37 million. It consists of 5 bedrooms, an absolutely equipped gymnasium and a dwelling theater. The ranch also will most likely be a money maker with crops, over 2,000 cattle and hundreds of wild mustangs.