China is moving forwards at an astonishing rate, but parents' preference for boys and the one-child policy have left a shortage of young women. Men of marriageable age are confronted by a shrinking pool of potential female partners - and the competition to find a bride is fierce.

Clutching his iced coffee, Peng Tai strolls down the street and disappears into a shopping mall.

Half way up the escalator, he surveys the scene below.

"What about that girl in a yellow dress?" I venture. "Uh uh, too short," he says.

And the girl in micro shorts coming out of a shoe shop? "No way. Too skinny."

"I am looking for girls with nice skin, nice white skin," he adds. "They should be not too thin and not too chunky with a normal way of walking."

A minute later he sidles up to a fashionable twentysomething girl trying on perfumes.

"Are you single?" he coos. "Looking for love?" She quickly shakes her head and walks away.

He gets the same brush-off from a few more young women - some look embarrassed, others impatient.

Peng Tai rejoins me by the entrance and sucks dejectedly on his drink. "The girls should not look angry. We do not want one with a sour face."

Suddenly he spots his prey - a very young girl in a sleeveless top with platform heels.

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Cautiously he approaches her, all smiles. She listens wide-eyed to his opening gambit and looks intrigued as he takes down her details.

Then, iPhone in hand, he moves in for the kill and snaps her picture in the doorway of the mall.

Peng Tai has a quota of three suitable girls a day. He is what is known as a "love hunter".

He works for the Diamond Bachelors' Agency, a Shanghai outfit which has hundreds of wealthy single men looking for wives on its books. The joining fees range from £15,000 to more than £1m ($1.6m) a year depending on the level of service required.

Peng Tai and dozens like him remind me of small fishing trawlers, scooping up what they can in their nets.

But their catch then needs to be specially prepared for the customer and China's billionaires are a notoriously fussy bunch.

One client insisted on a girl who looked identical to Zhang Ziyi, the star of the hit film Crouching Tiger, Hidden Dragon.

Image copyright Getty Images

Another, a real estate tycoon, paid the agency to search nine cities and interview 10,000 girls to find Miss Right.

More on China's marriage hunters Image copyright AFP Gong was bluntly informed that she was "not particularly beautiful or charming" and that "successful men couldn't possibly be interested" in her. "I felt very angry, so I asked a friend of mine how much it costs to make a website and I set up my own dating service," she says. China's number one matchmaker

Of course she had to be stunning. But she also had to be between 22 and 24 years of age and have a master's degree from one of the top universities in Beijing or Shanghai.

Peng Tai's work is performance-related but the rewards can be huge. The top love hunters can earn bonuses worth tens of thousands of pounds.

But I wonder if he ever worries about treating women as commodities?

"I do not care what the girls think," he says. "This is my job and we are providing a much-needed service."

While China's wealthiest men contract out the search for a spouse and have plenty of choice, at the opposite end of the scale some have no choice at all.

The country's inexorable economic rise has put marriage out of reach for many men.

These days grooms are expected to provide a car, a good salary and real estate.

One young engineer I met in a Beijing park, Zhang Junfei, told me that he would have to save up for 200 years to afford a one-bedroom apartment - and that is without eating or drinking.

Image caption Zhang Junfei and his mother at a marriage market in Jade Lake Park, Beijing

Men in the poorest, least-developed areas suffer the most from the skewed sex ratio because of another inescapable trend in modern China - mass migration.

In the past decade, 300 million people have left the countryside for the cities and for many young women it is a one-way ticket. They marry up and never return home.

There are 700 people in the village of Tanzhen in the mountainous Guangxi province. As many as 60 of them are single men - most expect to die bachelors.

Sitting in his courtyard, 30-year-old Wei Tianguang says virtually all the eligible young women are working in factories on the coast.

I ask if he has an ideal woman in mind. Any requirements?

"No requirements," he says. "I would marry any woman prepared to live here with me. Anyone at all."

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