Mar-a-Lago, Florida

Mar-a-Lago was originally built in 1927 by Marjorie Merriweather Post, heiress to the Post Cereal fortune. It has 126 rooms inside its 62,500 square feet. When she died in 1973, she left it to the National Park Service, which could not manage its upkeep, and returned it to her foundation. Donald Trump bought it a few years later for $10 million. It is on some lists as the 22^nd largest mansion in the USA, and the second largest mansion in Florida (after the 85,000 square foot Versailles, still under construction by David A. Siegel and his wife in Windermere).