Collector Joel Chung Yin-chai pulls out a red plastic box from behind his work station and takes out a piece of navy-blue fabric the size of a table cloth, bearing the jet-black calligraphy of the late "King of Kowloon".
The toothless, shirtless graffiti specialist hobbled around the city on crutches, clutching a dingy plastic bag of brushes and ink, writing on walls, lamp posts, electrical switchboxes, post boxes or any available surface in Kowloon and on Hong Kong island between the 1950s and the early 2000s.
Some called the imagery art, but others, including the Transport and Highways Department, regarded it as vandalism, swiftly removing it from public areas.
Opinions change. The government is now aiming to showcase a pair of wooden doors bearing the writing of the late self-proclaimed majesty, an artist more formally known as Tsang Tsou-choi, at the upcoming M+ museum, at the West Kowloon Cultural District.
Tsang is at the vanguard of a price boom in Chinese contemporary art. Collectors recently paid HK$120,000 for a smelly, worn-out T-shirt Tsang wore. Last month, a cream-yellow Vespa scooter festooned with his black-paint writing (see cover), sold for HK$1.84 million, a record for a Tsang artwork.
Tsang's writing emerged as a favourite of contemporary art collectors in an art boom in Hong Kong driven by mainland demand.
"It is a natural progression, like the Western world, that the mainland consumers taste the satisfaction of owning Louis Vuitton handbags, limousines, real estate, yachts, private jets and then move on to art, wine or collectables," said Angela Li, the owner of a gallery in Sheung Wan dealing in painting, photography and sculptures largely by contemporary mainland artists. Li, treasury banker by training, travels around the mainland scouting for new artists and art pieces. "They begin to appreciate art and climb the cultural ladder."
The Art Basel exhibition of modern and contemporary art debuted in Hong Kong in May after the organiser MCH Swiss Exhibition (Basel) bought a 60 per cent stake in Hong Kong International Art Fair in 2011 and transformed it into the biggest of its kind in Asia.
That deal, plus strong sales at the fair where individual Chinese artworks raised in excess of US$2.6 million, signalled a buoyant market.
"Contemporary art was not popular at all with many art collectors on the mainland when I started my business in 2001. It [contemporary art] emerged to be one of their favourites five years ago," said Li.
She added that the market got its first HK$100 million-plus artwork from a Chinese contemporary artist faster than expected.
She is referring to the sale of Zeng Fanzhi's Last Supper - an interpretation of the Leonardo da Vinci masterwork - that fetched US$23.3 million at a Sotheby's auction last month, a record for a contemporary Asian artist.
Nick Simunovic, managing director of Gagosian Gallery in Hong Kong - which represents Zeng and sells his work at the gallery - described the hammer-price as "astonishing".
"It shows that Chinese contemporary art is ready for its close-up on the global stage," he said. "The prices paid for masterpieces of Western and Asian art will continue to converge."
Mainland collectors will continue to be the dominant buyers of Chinese and Asian contemporary art, he added.
Inevitably, the question arises: is there a bubble brewing in the art world? Are collectors just chasing price gains, or do they fundamentally value the pieces they purchase for such astronomical prices?
Ominously, perhaps, at the recent Art Basel exhibition Chung witnessed bankers escorting Putonghua-speaking visitors around the fair in intense discussion on the valuation of items on display. "Painting, writing, or anything to do with arts, have become prey for speculators," he said.
Gallery owner Li said the art market has been buoyed by a stream of capital coming into Asia Pacific over the past few years. "So far, the art market is relatively healthier and more rational than the period between 2006 and 2008, during which any artwork that came under the hammer became an object of speculation," she said.
It bodes well for the market that collectors are appreciating artists such as Tsang. Stylistically, Tsang occupies the visual stream of Keith Haring of New York and Banksy of London. Like Haring, Tsang uses dense, irregular patterns that spiral out organically. Like Banksy, his main medium is graffiti, deploying witty, anti-establishment messages for all the public to appreciate.
Tsang's work is clever and beautiful in its way, but the pieces are not obvious items for collecting. They are challenging to own and appreciate.
A graffiti-covered Vespa can't be used to decorate a flat, for example, nor could a bed frame owned by and written on by Tsang, which was also purchased by a collector recently.
Collectors' interest in Tsang art suggest there is more fundamental appreciation underway in home-grown contemporary art with images and messages that resonate with people of this region.
Sotheby's has auctioned a piece of Tsang's art from Chung's collection every year since his first piece was sold in 2009. The first Tsang item put to auction raised HK$500,000.
In 2011, the boss of property-cum-media conglomerate Wheelock & Co, Peter Woo Kwong-ching, paid HK$800,000 for another Tsang piece.
Sotheby's auction in October of the HK$1.84-million Vespa was the first time a Tsang artwork breached the million-dollar barrier.
Chung, who holds the biggest collection of Tsang's work, has a vested interest in a rising market for Tsang originals. He nevertheless wants collectors to focus on the cultural value of the pieces, not the money angle, saying: "I hope collectors are more into the messages, the social and cultural dynamics he delivered in his work, rather than the appreciation potential."
Joel Chung is less a collector and more of an archivist of Hong Kong cultural objects.
His studio tucked away in the old industrial district of Sun Po Kong, holds heaps of furniture, stationery, toys, paintings, rubber stamps and students' scorecards from the 1960s. Most of his collection has scant market value, but it's meaningful for what it says about Hong Kong's history.
When Chung met Tsang Tsou-choi 25 years ago he could scarcely imagine the artist's erratic, if arresting, public scrawling would someday be worth millions.
One hot afternoon on Nathan Road in 1989, Chung saw a crowd surrounding a "half-naked old man" - Tsang. Tsang clutched a bucket of black paint in one hand and wielded a brush with the other with which he wrote "King of Kowloon" and some names on a utility box. Chung discovered later the names were of Tsang's family tree.
Chung, who had seen the calligraphy elsewhere and wondered who the writer was, was finally face to face with the mystery figure.
He was fascinated by Tsang's style - he wrote in black, bold fonts without any punctuation - and by his persona: Tsang called himself a king, his wife, queen, and his children, princesses and princes.
It was a cunningly subversive message. In those days the British had authority over Hong Kong, and Queen Elizabeth was its head. But here was a native proclaiming his own, and arguably more legitimate, sovereign authority.
Tsang used to live with his wife, Man Fook-choi, but in his later years lived alone in Kwun Tong. He rarely took a shower, and his filthy, cluttered home was a permanent fire hazard. A fire did in fact break out, forcing Tsang to move to a home for the elderly.
Many of Tsang's contemporaries thought he was insane, not least because of his claims to royalty while living on government welfare subsidies.
"No one can judge if he was nuts or not," says Chung, who has spent the past six years combing through historical, social and cultural information of the era in which Tsang grew up and worked.
Without any proper training in art and attending a primary school for only two years, Tsang reflected the culture of his times.
"He was in a constant battle for his primary identity as the King of Kowloon. He told me repeatedly his ancestors owned many sites in Kowloon but were taken away without compensation," Chung says. "This can't be proven, but he kept writing what he believed."
Chung recently discovered that writing on walls was common practice in the 1920s-30s, when Tsang was young. His calligraphy style also reflected his era. Confucian theology underpinned the academic curriculum of this time, and Confucius' writing was unpunctuated, with some fonts made bigger and some smaller to emphasise certain meanings.
"Some collectors may not care about Uncle Choi's background, nor about what or why he wrote, but the social, historical and cultural elements can be read between the lines," Chung says, using his nickname for Tsang.
After Tsang's demise, Chung inherited some 300 pieces. Many of the works are valuable as art, some make an important statement about Hong Kong history, but some are just bizarre.
"Some are not as worthy as you think," he said, taking out a piece of yellowish paper on which Tsang wrote, in English, "WHAT'S GOING ON SNOWMAN SANTA CLAUS."