The previous owner, horse trainer David Hayes, bought the property in 1989 for $610,000.
The bidding opened at $4 million, with Waterhouse competing against Racing NSW CEO Peter V’landys during the auction.
Decked out: The 66-year-old horse trainer s new freestanding Victorian home features stables with eight horseboxes
Bare necessities: The house itself is situated on a 613 square metre block and boasts four bedrooms with two bathrooms
However Waterhouse came out on top, adding to her portfolio that already includes the properties on either side of her new acquisition.
The purchase comes after Gai got candid about her fraught relationship with her famous father on Anh s Brush with Fame on Tuesday.
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