Princess Eugenie and Princess Beatrice's childhood home has remained empty since undergoing a multi-million-pound rebuild two years ago.
Angry neighbours described it as an "eye sore" that resembles a supermarket.
Sunninghill Park in Berkshire was sold by Prince Andrew to Timur Kulibayev, the son-in-law of the former president of Kazakhstan, Nursultan Nazarbayev, in 2007 for £15million.
After falling into a state of disrepair, the property was demolished in 2015 and a new, lavish home was constructed.
Princess Eugenie and Princess Beatrice grew up in Sunninghill Park
Getty
According to sources, the project cost close to £18million.
Work was completed two years ago, but despite the eye-watering prices involved, nobody has lived in Andrew's former home since the repairs.
Metal shutters on the windows have remained down with large iron gates at the entrance.
One neighbour told The Mail: "I don't blame the owners for not wanting to live in it because it's so horrible. I've heard that it's very luxurious inside but what good is that if the outside is so revolting?"
The Duke and Duchess of York moved to Sunninghill after their wedding
PA
The empty property is patrolled by a team of former Gurkha soldiers.
Five gardeners work at the property to maintain the grounds while a team of cleaners visit each month.
An official at the property said: "The cleaners are the only ones who go into the home regularly. I've been working here since it was rebuilt, and I've never seen the owner or any of his friends or family.
"None of them have ever stayed the night here. It seems like a lot of money to spend on a luxury home that you are never going to use. It's a bit of a mystery why they've never come here."
Sarah Ferguson bringing Beatrice and Eugenie home to Sunninghill in 1993
PA
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Sarah Ferguson and Prince Andrew divorced in 1996GettyAnother neighbour told the publication: "It's very ugly and looks like a large supermarket in an out-of-town shopping complex.
"It doesn't fit in with the surrounding area and has completely ruined the view of a stunning park.
"The only plus point is that it's behind a high wall and trees have been planted around it which hopefully will grow tall and hide it. I have to say it's the most disgusting building I have ever seen."
Another local resident said: "It looks like a supermarket or a large budget hotel. We've never seen or met the owner, or his family and the only people coming or going are the staff."