As the creator of some of America’s most opulent mansions Frank McKinney knows a thing or two about luxury. So when it came to marking his 45th birthday, the flamboyant tycoon was likely to treat his guests to an extravagant party.

Indeed, a tour of his latest construction — a $29 million (£15 million) affair in Manalapan, Florida, with glass staircases, fish swimming in the ceiling, indoor waterfalls and two wine cellars, one for red and one for white — proved a perfect start to the three-day celebration. Then came dinner and champagne at his beachfront estate near by.

But there was barely time for the maverick millionaire’s 55 guests to sleep off their hangovers before they were whisked away for the next phase of his $5,000-a-ticket birthday experience — a sobering trip to the festering slums of Haiti. The Tour of Extremes took them from Florida’s Palm Beach County — among the nation’s wealthiest communities — to Cité Soleil, the poorest suburb of the poorest city in the western hemisphere’s poorest country.

There, Mr McKinney has built more than 500 homes for 4,000 people living in abject poverty through his charity, Caring House Project Foundation. His guests’ ticket money will fund the construction of 55 more.

“It’s not everyone’s idea of a birthday, but it is mine,” he told The Times. “I’m a modern-day Robin Hood. Here I am providing property to the world’s most wealthy; should I not be providing it to the world’s poorest and homeless too?”

Mr McKinney, who started working life with $50 to his name and who now creates properties worth up to $135 million, is a regular on the motivational speaking circuit, giving tips on how to succeed in real estate.

A brazen self-promoter, he even sells $250 talking action figures of himself — in aid of his charity — which come complete with his trademark long blond hair and which spout his mantras: “Make it big!” and “Don’t let fear stop ya!” His favourite, though, is: “Be sure to share your blessings with others.”

With stomachs still groaning from their birthday banquet, Mr McKinney and his friends — largely business owners and real-estate entrepreneurs — toured the Haitian capital, Port-au-Prince, passing roadside stalls that sold cakes made of mud to fill the stomachs of the starving.

In Cité Soleil, a squalid shantytown where 300,000 people live without running water, electricity or sewage disposal, violent crime and gang wars are commonplace and few outsiders will enter without an armed United Nations escort. But to those he has helped there, Mr McKinney is known as “Bon Papa” and greeted as a hero.

“Here in the US, people miss one episode of Desperate Housewives and they have to go and see their therapist. In Haiti, they have so little yet they are a faith-filled and happy people — they are desperate, but also full of hope,” he said.

“When you take care of sustainable needs like housing and water, they flourish. It has an impact on generations, not just the here and now.”

Angel Aloma, executive director of Food for the Poor, a US charity whose feeding centres in Haiti have received thousands of tonnes of rice from Mr McKinney, said: “His contributions are nothing short of huge.”

In a final cultural twist, Mr McKinney and friends wound up their tour with a night at Haiti’s five-star Hotel Montana, where they ate birthday cake and partied to a calypso band.

“You can have maybe a handful of epiphanous moments in your life and the Tour of Extremes was one, for almost every one of those 55 people who came,” he said. “When they shared their reflections afterwards, not a single one mentioned the mansion or the hotel. They spoke about Haiti.”

Mr McKinney says that he takes his inspiration from “biblical wisdom”. A parable in the Gospel of Luke, is paraphrased into a personal motto: “To whom much is entrusted, much will be expected.”

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