She then rented the house to a tenant, who has now bought the property from the Duchess.
James Henderson, her spokesman, said last week: “[She] wasn’t looking to sell it.
“She was asked by the tenant to buy it and it seemed like a good time to sell. It’s an investment property for her girls and so the monies will be reinvested accordingly.”
The 10% loss is in line with a general decline in the property market in London in the past five years.
The Coutts London Prime Property Index, published earlier this year, cited “more pronounced discrepancies” in the Knightsbridge and Belgravia areas, where they said pricing “is still over 20% below the height of the market in nominal terms”.
The Duchess initially bought the mews house from the Grosvenor Estate of the Duke of Westminster – one of the richest men in Britain.
The news of the sale comes as the embattled Duke and Duchess of York are back in the headlines for their historic association with the convicted sex offender Jeffrey Epstein.
Last week, the Duchess was dropped by a number of charities as patron and ambassador over her email correspondence with the late paedophile.
Organisations, including the British Heart Foundation and the Teenage Cancer Trust, announced their decision to end their association with the Duchess, 65, following reports that she described Epstein as a “supreme friend” in 2011, after he was convicted of procuring a child for prostitution.
Henderson said that she had written the email because Epstein had vowed to “destroy her” in a “Hannibal Lecter-style” phone call.
In recent years, the Royal couple have also faced pressure from the King to vacate their 30-room Royal Lodge home and move into the more modest Frogmore Cottage, the former home of the Duke and Duchess of Sussex.
However, in November last year, it emerged they had raised the funds to remain at the £30m estate, but it was unclear where it had come from.
The Duke’s Crown Estate lease gives him the right to live in the Grade II-listed property until 2078, but the contract includes a clause that he must maintain it to an appropriate standard.
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