Bill Gates' former waterfront mansion on Florida's exclusive Jupiter Island is on sale for $23.5 million. See inside.

The home was owned by Bill Gates' investment entity from 2009 to 2018.

Steven Martine Photography, Inc /ONE Sotheby's International Realty

• A mansion once owned by Bill Gates on Jupiter Island is for sale.
• Gates' investment entity bought it in 2009 for $5 million and sold it in 2018 for $4 million.
• Now the house is on the market for $23.5 million, an increase of $19.5 million.

A 9,458-square-foot mansion once owned by Bill Gates just hit the market, and if you have $23.5 million to spare...