As a child in Singapore, author Kevin Kwan remembers going to a family friend's house, where his father played tennis. Next to the tennis court was an airplane hangar with a private jet casually sitting in it.

At the house of another family friend, he saw at least 15 exotic cars - among them vintage sports cars and Rolls Royces in all colours of the rainbow - parked in perfect rows along the estate's portico.

"It was only looking back that I realised how unusual that is in Singapore," says Kwan, the best-selling author of comic novel Crazy Rich Asians and its sequels. His first book gave readers an insight into the world of insanely wealthy Singaporeans and is being adapted into a movie by Warner Bros.

"As a child, you're cloistered in this world," the 43-year-old says on the telephone from New York, where he lives. "You don't know how other people live until you leave that world and realise not everyone has an airplane in their garage."

He insists that he himself is not a "crazy rich Asian" like the outrageous figures he portrays in his books, although he is from a well-connected family.

Born in Singapore, he grew up in a multi-generational family home in Bukit Timah and went to Anglo Chinese School (Primary) until he was 11, when he emigrated to Texas with his engineer father, piano- teacher mother and two older brothers. He is now an American citizen.

Kevin Kwan's first two books CRAZY RICH ASIANS (2013) Doubleday Paperback/527 pages/$28.34/Books Kinokuniya When Chinese-American economics professor Rachel Chu is invited by her Singaporean boyfriend, Nick, to attend his best friend's wedding back home, she imagines it will be a warm family affair. Little does she know that Nick is a scion of one of Singapore's wealthiest families and that his rich, scheming family will do whatever it takes to get Rachel out of the way - none more so than his domineering mother, Eleanor, who is determined that no American girl from a humble background will steal her only son. CHINA RICH GIRLFRIEND (2015) Doubleday Paperback/479 pages/$28.36/Books Kinokuniya Rachel and Nick are about to get married when Nick's mother, Eleanor, gatecrashes their simple Californian wedding by helicopter, having just dug up information that Rachel is in fact the illegitimate daughter of one of China's wealthiest men. When Rachel travels to Shanghai to meet her birth father, she is thrust into a dangerous world where people are not just rich, but "China rich" - where spoilt heiresses have millions hanging off their every Instagram post, artworks are auctioned off for hundreds of millions of dollars and money alone is not enough to get into the highest echelons of mainland and Hong Kong society.

His grandfather was Singapore's first Western-trained ophthalmologist, Dr Arthur Kwan, who was for many years the commissioner of the St John Ambulance Brigade and was knighted by Queen Elizabeth II.

Dr Kwan shared a clinic with his brother-in-law, Dr Hu Tsai Kuen, father of Singapore's longest-serving finance minister, Dr Richard Hu.

Kwan's books, for all their riotous humour, have grief at their source.

His father died in 2010 after a long battle with cancer, during which Kwan took 18 months off his work as a creative consultant to care for him. During this period, they would chat about old times in Singapore.

"To be such a close witness to the intimacy of death is a profound, life-changing experience," says Kwan. "The books would never have existed had I not gone through that with my father."

He began writing what he thought would be dramatic stories based on his memories, as a way to cope with his father's death, but a funny thing happened along the way.

"Somehow, as it spilled onto the page, somewhere between my mind and my fingers meeting the keyboard, the story got transformed and became very satirical.

"For me, it was a very healing experience to be able to channel my grief and my memory in a way that brings laughter and joy."

The seed of loss planted in the books from their inception fully flowers in Rich People Problems, the trilogy's final instalment, which came out in Singapore last Tuesday.

It finds the Shang-Young clan's matriarch Shang Su Yi on her deathbed, as her multitudinous descendants jockey for last-minute favour in the hope of inheriting her 64-acre (26ha) estate, Tyersall Park.

Su Yi's one-time favourite grandson, Nick, whom she disowned when he married Chinese-American economics professor Rachel Chu, returns to Singapore to make amends - provided he can fend off his fortune-crazed relations first.

Such last rites are a fitting end to the series, which began with the wedding of the century in Crazy Rich Asians. "I thought a wedding and funeral would be perfect bookends for this sprawling saga," says Kwan, who is single.

The books are famous for their mind-boggling displays of wealth - in the first book's opening, the family responds to a British hotel concierge's racist treatment by buying the entire hotel - but Kwan insists that the truth tends to be more extravagant than fiction and, in fact, his editor often made him tone things down.

Many of his characters are inspired by individuals he knows, while others are amalgamations of different personalities. But he remains tight-lipped about whom they are based on, among them Astrid Leong, the incredibly beautiful and intensely private heiress dubbed "the Goddess" by her peers.

Kwan recalls that the film producers, while scouting locations in Singapore and Hong Kong, would be approached at parties by dozens of women, each claiming to be the inspiration for Astrid. "It's very flattering that people feel so strongly about my character that they would want to claim to be her," he laughs.

The character he feels he is most like is Alistair Cheng, Nick's "misunderstood, creative cousin" who produces films in Hong Kong, to the chagrin of his extended family.

"My relatives have always been wondering - what is Kevin actually doing in New York?" says Kwan, who studied media studies and creative writing at the University of Houston and also has a Bachelor of Fine Arts degree specialising in photography and visual communications from Parsons School of Design.

"Most of them couldn't figure it out for the longest time and probably still can't."

He does not often return to Singapore, although when he does, he goes in search of a good wanton mee, which he says is impossible to find in New York.

His favourite hawker joint is Newton Food Centre. "That's probably blasphemous for a true foodie, but that's the one that was closest to where we lived and so I have the fondest memories of it."

Kwan, who, as a creative consultant, worked on projects such as a website for media organisation TED and a coffee-table book for talk-show star Oprah Winfrey, has given this career up to write full-time. He is now working on the script for a television drama for STXtv, the TV division of US company STX Entertainment, where he will serve as showrunner.

While he will not disclose what it is about, he says it will take place outside the Crazy Rich Asians world and he intends for it to carve out even more onscreen opportunities for Asian talent.

"It's always been my focus to bridge the gap between East and West," he says. "To create stories, films and TV that the reader or viewer can really lose themselves in, that transcend race and skin colour - that to me would be the ultimate triumph."

•Rich People Problem ($26.54 for paperback, $46.30 for hardcover) is available from Books Kinokuniya.

Crazy Rich Asians, the movie

Crazy Rich Asians author Kevin Kwan understands some of the frustrations surrounding the film's casting choices, such as the decision to cast Eurasians Henry Golding and Sonoya Mizuno as ethnic Chinese characters, but feels that the producers have achieved the best balance of talent possible.

"People are so eager and excited and sometimes disappointed by casting choices because, historically, there have been so few opportunities for Asian actors in mainstream Hollywood and Western- produced films," says Kwan, who is involved in all the film's aspects, from choosing screenwriters and casting to costuming and production design.

"We really tried as best as possible to be thoughtful and intentional with our casting. But at the end of the day, everything is such a balancing act," he says, adding that there are numerous factors to consider when casting, including actors' availability and chemistry.

"To be able to get 20 of the top Asian actors around the world to commit to a two-month window - it's been miraculous that we've been able to achieve it."

The film is being produced by Color Force and Ivanhoe Pictures.

Kwan says he and American director Jon M. Chu are taking it seriously that the actors, who hail from all over the world, get their Singlish right. "I can't tell you how much we agonise over every single casting decision and some of that was dependent on whether the actors could master the accent they are required to master. That said, some people might not be satisfied anyway."

Here are some of the cast of Crazy Rich Asians:

Constance Wu as Rachel Chu

American actress Wu, the star of ABC sitcom Fresh Off The Boat, plays Chinese-American economics professor Rachel Chu.

Michelle Yeoh as Eleanor Young

Malaysian actress Yeoh, best-known for her role in the movie Crouching Tiger, Hidden Dragon, plays Nick Young's domineering mother, Eleanor.

Henry Golding as Nick Young

The Singapore-based host-presenter makes his film debut as Nick, heir to the Young fortune and Singapore's most eligible bachelor. Golding's father is British and his mother is from the Iban tribe in Sarawak.

Gemma Chan as Astrid Leong

British actress Chan, from television show Humans, plays Astrid Leong, Nick's stunning yet down-to-earth cousin, whose picture-perfect life hides cracks.

Pierre Png, Fiona Xie and Tan Kheng Hua

So far the only Singaporean actors who have been cast in the film, albeit in undisclosed roles.