We made all the furnishing decisions together,” says Paul Darbyshire, discussing the rather remarkable interior of his Notting-hamshire home. “Otherwise, world war three would have broken out.”

The property that the inveterate antiques-collector and horse-breeder is referring to is Grade II*-listed Ranby Hall, which dates from 1740 and sits three miles away from the Georgian market town of Retford. It is where he and Paul Wyatt have created a stunning showcase for exquisite furniture, paintings and all things collectable.

As we drive up to the hall and step from Darbyshire’s navy-blue, shag pile-carpeted Bentley, the two magnificent Georgian facades inspire awe.

“At first, we had fallen in love with a house just outside Lincoln, but we didn’t get it,” Wyatt says. “When we first saw this place, I thought it was a bit big for us, but Paul jumped up and down.” Big the three-storey pile certainly is: it has eight bedrooms (some of which are suites) and eight reception rooms. Yet when Darbyshire, 43, and Wyatt, 48, bought it for £650,000 13 years ago, there was plenty to be done. The hall had been repossessed, and was in poor condition: they estimate that they have spent more than £1m restoring it.

The couple – who met on a blind date 15 years ago – reroofed and releaded the place, insulated the walls, rewired, replumbed and reinstated all the plaster mouldings. Cream and pink marble floors were laid throughout, and the walls of nearly every room in the 14,690 sq ft home were treated to hand-blocked, handmade coverings from Colefax & Fowler and Osborne & Little.

Originally the dower house to the Duke of Newcastle’s nearby Clumber estate, the hall today sits on seven acres, with verdant lawns, a walled garden and a carp-filled lake. The couple lease another 100 acres around the house (and own 120 nearby) for their business, Ranby Hall Stud. They are successful breeders, producing top-class animals for eventing, hunting and racing, with about 115 mares, foals, ponies and stallions on the books.

But the time has come to downsize not only their highly profitable business, but their living space. For the Brighton-born Wyatt – whose previous incarnations include flower-shop owner and City banker – was nearly kicked to death by a mare two years ago. Thankfully, he didn’t die – as doctors had predicted – from internal bleeding, but he did come close to losing an eye. “I was in the Savoy, having a lovely lunch, when I heard,” Darbyshire recalls. “I thought they were joking. I left the hotel without even checking out.”

Wyatt has made a good recovery, but his memory has been affected, and some days, his eyesight is problematic. “I know I’m not perfect,” he says, “but I manage.”

Darbyshire, meanwhile, says that although horses are in his blood, he won’t ride any more, and has to take special care working with them: “I can’t afford to get maimed or hurt.”

Wyatt stays at home as much as possible, as he feels comfortable and safe in the sumptuous house. On the ground floor, what is officially known as the state dining room is used as the drawing room: elegant cream-and-gold columns and arched doorways provide sightlines to other formal entertaining areas on either side. Secret staircases, now blocked up, are built into walls behind doorways and lead to the old servants’ quarters.

The original kitchen, on the ground floor, is now the tack room; the private chapel has been converted into a cosy cooking area. Wyatt had its cherrywood and etched-glass cabinets made to Biedermeier designs by a Lincoln firm, and they give a warm, intimate feel to the 9ft 2in x 9ft kitchen. “I paid £25,000 for it 11 years ago,” he says, “but it has stood the test of time.”

Next door is a small sitting room, the domain of Dorothy, an ancient, blind border terrier, and a crew of other dogs and cats. It’s the sort of room you would imagine the Queen providing for her corgis at Balmoral: all cosy chairs, instead of baskets, and thick blankets. In it hangs one of the couple’s many paintings by Malcolm Coward, an equestrian artist. “It shows the joy of riding out,” says Wyatt, who, these days, doesn’t often saddle up. There is also a bulky old television. In fact, nowhere in the house is there a modern plasma screen: “We don’t believe in the contemporary-old style.”

Up a floor, via the marble and wood staircase that Wyatt and Darbyshire installed, is the dining room. It is a cleaner’s nightmare: objets d’art, cabinets, silver trays brimming with booze, European busts dripping with costume jewellery (an expensive passion of Darbyshire’s). As with all the reception rooms, the mood is one of opulence. There is a huge English dining table, the only piece of Victorian furniture in the house; a chinoiserie cabinet with intricate interior drawers rests on a carved English table; and the rare blue-and-white porcelain Chinese garden seats (once owned by Lady Marks, of Marks & Spencer fame) are particular favourites, as are the silver food domes, which came from the Benacre estate, in Suffolk.

The russet-marble fireplace was brought back in a van from Bordeaux, as was the immense gilt mirror above it – when Darbyshire and Wyatt go shopping for antiques, they take a truck.

“If I like it, I’ll buy it,” says Darbyshire, who comes from a “horsey” Harrogate family. The pair find their furnishing gems in all sorts of places. It might be an auction house such as Bonhams, a country estate selling off furniture, or even a skip.

Darbyshire takes care of the domestic chores (“I’m horses and house,” he says), with occasional help from a cleaner. Though valuables abound, he’s not precious. “It’s a house, not a palace. People break things.”

Still, some incidents do rankle. One domestic employee was fired after somehow putting a chair leg through the portrait of a Borgia lady – complete with poison ring and gloomy background – that the couple had bought at a Grosvenor House art and antiques fair. And he shudders at the memory of the inebriated dinner guest who smashed a 17th-century Chinese bowl.

The room has seen many a lavish party, and again Darbyshire is in charge. “It’s as easy to cook for 12 as it is for two,” he says. The couple used to have a chef and three girls to wait at table, but cut down on staff after Wyatt’s accident.

Darbyshire’s boudoir is also on the first floor. In the dressing room, with its bronze-inlaid fireplace, fur coats are slung here and there over antique armoires. They are another indulgence, he ruefully admits: “Sometimes the animal-rights protesters outside Harrods sway me, but only for about an hour.”

Wyatt, who has had trouble sleeping since the accident, has his own simply furnished bedroom and sitting room on the second floor – once the servants’ quarters – so he doesn’t disturb Darbyshire. The five guest bedrooms are also on this floor.

A squash court, tacked onto the house in the 1920s by one owner for her younger, athletic second husband, adds a touch of decadence. The original wooden flooring and glass roof are intact, but it is now used as a storeroom; hanging above dusty, cobwebbed furniture are chandeliers put up for a dance the pair threw one year.

Will there be time for another one before Darbyshire and Wyatt move? Ranby Hall is for sale as a whole for £2.85m, or in four lots (there is more accommodation in the coach house and stables). About 70 brochures have been sent out, says Helen Bennett, East Midlands country-house co-ordinator at Humberts, the estate agency and chartered surveyors marketing the property, and both developers and people looking for a family home have shown interest. “The unique thing about Ranby Hall,” she says, “is that you feel as if you are in the middle of a beautiful estate, without the huge acreage to look after.”

For Wyatt and Darbyshire, parting with the amazing home they have created is not easy. “I’d hate to see it broken up,” Wyatt says. “Plans drawn up by friends a couple of years ago, breaking it into 14 pieces, have sat unopened on the stairs.”

The pair haven’t decided where to go next, although Scotland is a possibility. “When we first came here, we lived on a building site,” Darbyshire says. “I’m not doing that again – although I was the one who pushed Paul into buying it.” This may be a matter for debate. “It’s quite likely I would take that on again, actually,” Wyatt says thoughtfully. “I don’t like living in other people’s chaos.”

Ranby Hall is for sale for £2.85m with Humberts; 01476 514500, www.humberts.co.uk

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