Four years ago he and his business partner William Read stumbled — they were on a walking holiday in Andalusia — on a ruined barn in the mountains between the Mediterranean and Granada. A sign daubed in red paint on the door read: Loco Dentro. Muerte Seguro. “It means ‘Madman Inside. Certain Death’ but, at the time, we thought it might mean the place was for sale,” King recalls.

The pair had been planning to build their own home for a few years. After making a series of unsuccessful offers on land in England — “even the smallest plots in East Anglia were too expensive” — they decided that a Spanish “ruin of death” was just what they were looking for. After two weeks negotiating with refreshingly sane local peasant farmers, four walls, a collapsed roof and an enormous pile of goat’s manure were theirs.

Next week, the 42-year-old former teacher and the 45-year-old garden designer will finish the neat edging on their British-style lawn and plant the first Bramley apple tree in Spain from a cutting they smuggled into the country in a carrier bag. Then they will raise a glass of vintage cava to one of the savviest self-build deals on the continent.

The figures alone are enough to make anybody struggling to get on to the property ladder in Britain weep. King and Read paid £50,000 for the ruined building, named Cortijo Opazo, and three acres of terraced land, fed by melt-waters from the glaciers of the Sierra Nevada. Over the past 18 months they have spent £95,000 rebuilding the house and re-landscaping the grounds.

They have added a second storey, a new wing, a courtyard and two terraces to the property, which is near the village of Pitres, about 12 miles from Orgiva and an hour’s drive from Granada. There are now four bedrooms, three kitchens and four bathrooms. The new garden is half-English, half classical Moorish. The formal slate-clad pond with a fountain is offset with myrtle hedging, similar to that found in the grounds of Granada’s Alhambra Palace.

King and Read say that the view from the garden over the mountains to the sea is priceless but the actual cost is £145,000. “I know that building your own home for less than the price of a boxroom in most British cities sounds too good to be true but that’s what happened,” says King, as he pours himself a glass of the “awfully good and only €2 a bottle” local Costa Rosé wine.

If King feels smug — and he is one Essex man on the Costa who has every right to boast about his property — he’s not showing it. He is quick to point out that building your own home in Spain takes years of financial planning, hard work, and a healthy dose of good luck when it comes to dealing with Spanish practices.

“We had to save and save for a deposit,” he says. “We sold one house in Essex and rented out a flat in Leytonstone before we had the money to buy the ruin but that’s all we had: a ruin. We camped on the land for three months as we helped to clear the overgrowing vegetation. We had no electricity and only cold spring water to wash in. When the temperature got down to minus 6C at night in December and a storm flattened the tent, we were forced to move in to a flat in a local village.”

Horror stories of stifling bureaucracy, lax working practices and shoddy building are enough to persuade most British buyers to build a home anywhere but Spain. King says it can be tough, but the trick is to act as project managers, rather than DIY experts, and to hire a local translator-cum-fixer.

“For even an experienced DIYer, building in Spain can be tough. DIY is just not part of the culture. There are no big building suppliers. So the first thing we did when we arrived was decide to be project managers, not manager- contractors.” To help them, King and Read hired a British-born fixer, Barbara Lynch. “She lived locally and knew everybody. She found some good local builders and then gave us a crash course in the Spanish way of doing things.”

Among the tricks Lynch taught King and Read were: never have a site meeting with builders before 11am, when they have their breakfast. “Food improves their mood,” King says. Never expect builders to work when it rains — even indoors. Accept that a Spanish right angle isn’t always exactly 90 degrees. Build like the locals build — slowly and using traditional materials. Always go to the bank or the post office just before siesta time when service picks up dramatically. And, if at first you don’t succeed with the Spanish bureaucracy, be a bloody-minded Brit until you get what you want.

“We wouldn’t have done half of the things we needed to do without Barbara,” King says. In fact, King and Read would probably still be in the dark. “To get hooked up to the electricity network, we needed a permit from the local town clerk. He said yes, but then did nothing, then there was a fiesta, then he was sacked, then he was reinstated, then he told us that we needed permission from another person, then it was Easter.

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