If you want to be the cream of the property crop a former dairy parlour in Mayfair – with a £25million price tag – could prove an ideal cash cow.

It is the most expensive farm-to-residential conversion ever undertaken in the UK and will see the Farm Street site transformed into a mansion with more than 8,000sq ft of space.

Developer Wetherell is at the helm of the project. It has milked the property’s historic features for all they’re worth – including sprucing up the stone facade and three-storey double fronted brickwork – in an attempt to tempt wealthy buyers.

Chief executive of Wetherell Peter Wetherell said: “This recently built house is an outstanding example of contemporary living in historic Mayfair at its very best.

“As the location of Mayfair’s dairy, the interesting and unusual history allowed for the construction of a property on a commercial depot site, without the usual restrictions of historic listing controls.

“The result is an open flowing family house providing spacious rooms and generous ceiling heights rarely found in historic Mayfair.”

Living space has been spread across six floors with both a sweeping spiral staircase, a second set of stairs and private lift to facilitate travel between them.

Buyers with a keen eye for detail will appreciate the inner hall’s impressive coffered ceiling and marble flooring as well as three sets of French windows, opening onto balconies, on the first floor.

The collection of five bedrooms includes a master and VIP suites with en suites and a guest bedroom that benefits from a dedicated walk-in wardrobe. Further indulgence abounds with a swimming pool complex, steam room, gym and terraces.

A fully integrated sound, TV and cables system connects every level with comfort cooling and underfloor heating installed in all main rooms. The freehold price is £25,000,000.

Call joint agents Wetherell on 020 7529 5566 or go to wetherell.co.uk or Knight Frank on 020 7499 1012 or go to knightfrank.co.uk .