Mary-Jane Rathie, 43, inflated her valuations of luxury properties in some of the most exclusive areas of London and was convicted of fraud at the Old Bailey.
Rathie, of Waltham Cross, Herts, got money and cars to "inflate" valuations to help secure the loans.
She was convicted of five counts of fraud between May 2007 and June 2009 and of concealing criminal property.
Her husband, Met Police officer David Rathie, of Cheshunt, was cleared of a charge of concealing criminal property.
Two luxury cars worth a total of £200,000 - a Bentley Continental and Range Rover Sport - were said to be registered in the name of the officer, who worked with the central London traffic unit, the jury heard.
£100,000 wedding gift
Judge Timothy Pontius warned Rathie, who denied the charges, that she faced imprisonment "of some length" when she is sentenced on 27 July.
David Durose, prosecuting, told the court that the surveyor, who worked with Ashdown Lyons, provided "dishonestly-inflated" valuations for a woman, who used them to secure mortgages from the Bank of Scotland.
The offences relate to a riverside property in Chelsea; a flat in Belgravia, near Sloane Square and another at Chester Mews, at the back of Buckingham Palace, the jury heard.
A fourth property was in the Docklands, east London, and a fifth in Pimlico, central London.
Rathie's client, known as Joanne Pier, has since left the country and cannot be found, the trial heard.
In June 2007, Rathie reported to managers she was offered £100,000 as a wedding present by Ms Pier, which she had declined, but the situation changed six months later, the jury heard.
