Zhang says eBay is the biggest used car website in the United States; it sells one-third of the country's second-hand vehicles.

"Car sales were booming in 2002 and 2003, but the replacement cycle usually takes about five years. The best time for used car sales will come in 2007 or 2008," he says.

A lack of support services for used car sales has become a big problem, however. Many used models are either stolen or smuggled, and owners usually modify their cars before selling to others, so buyers are usually very cautious. But fortunately, most multinational automakers understand the potential of the used car market, and many have already begun building their networks.

Volkswagen started a used car programme in 2004 to accredit its provide after-sales services.

The German manufacturer has two auto production joint ventures in China, and has been the leading automaker on the mainland for about 20 years. It has sold three million cars, and its older models have become the biggest source of used automobiles in the country.

General Motors, Ford, Nissan, and other big names have also established programmes to encourage buyers to replace their old cars with new models.

EBay has also started building partnerships with automakers, testing organizations, and credible dealers to organize and promote used car bids on its website.

Last August, Shanghai Volkswagen, its dealers and eBay China organized two bids for 55 used cars.

"Online auctions of used cars just started in China, but it can become a very good business," says Zhang.

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