14. Xanadu 2.0, Seattle, Washington
When the discussion is about the most expensive houses, then how can we forget to talk about billionaire Bill Gates’ mansion? He owns one of the most expensive and high-tech houses of the USA. Xanadu 2.0 is a Pacific lodge style mansion on the hill side, overlooking Lake Washington. The 66,000-square feet property is famous for its architecture and the modernized technological amenities that it possesses. The exotic lodge is located in Medina, Washington and according to 2012 tax assessments; its market value is estimated to be $120.5 million.
The house contains a huge library, 2,500-square feet gymnasium, 60 feet long swimming pool with underwater music system, and an automatic temperature, music, and light adjuster. Xanadu 2.0 is a perfect example of an earth-sheltered home.