Flush with cash, Chinese homebuyers are flooding into the U.S. housing market, and paying top dollar.

"The Chinese came out really huge in the past year," said Jonathan Miller of Miller Samuel, a New York-based appraiser.

Chinese buyers accounted for 18% of the $68.2 billion that foreigners spent on homes during the 12 months ended March 31, according to the National Association of Realtors.

At a median price of $425,000, the Chinese are also buying more expensive homes than other foreign buyers, who spent a median of nearly $276,000 on U.S. homes. And nearly 70% of those pricey Chinese deals were made in all cash.

Nowhere is the influx of Chinese homebuyers felt more strongly than in California, where more than half of the homes sold to foreign buyers went to Chinese nationals.

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Sally Forster Jones, an agent with Coldwell Banker International in Los Angeles, said Chinese are snapping up many of the trophy properties on the city's Westside. She estimates that she's sold about 10 multi-million dollar homes to Chinese nationals over the past 12 months.

"The uptick in sales to Chinese buyers started several years ago but it has increased dramatically lately," she said.

Most of her Chinese clients are wealthy industrialists or real estate tycoons, many of whom spend less than half the year in the States.

"Some have children going to school in Los Angeles and use the homes as residences for them and [as a place] to stay at when they visit their kids," said Jones.

China's gross domestic product has grown by high single-digit, sometimes double-digit rates for the past 10 years, producing a lot of cash for the country's top business people who view U.S. real estate as a safe and stable investment.

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Top 5 countries for foreign buyers of U.S. homes Country % of sales to non-U.S. buyers 2013 Median price spent Canada 23% $183,000 China 12% $425,000 Mexico 8% $156,000 India 5% $300,000 United Kingdom 5% $250,000

Rick Turley supervises real estate offices for Coldwell Banker in eight counties in and around San Francisco, including Silicon Valley. Many of his Chinese clients work in technology.

"The current hot spots are Palo Alto, Menlo Park and Cupertino, near Apple headquarters," he said.

Most purchase the homes to raise their family and they pay special attention to the local school systems. Turley also has Chinese clients who buy homes for their kids. Last year, a family from Shanghai bought a condo for their daughter who was attending Stanford. The daughter has since graduated and now works at Google, he said.

Many Chinese buy homes through the U.S. government's EB-5 Immigrant Investor program, which is considered a fast-track to getting a green card. To qualify, foreigners must invest at least $500,000 in a business that provides or preserves 10 jobs. This could be a home that is part of a bigger business project, such as a condo complex. Nearly 80% of all EB-5 visas went to Chinese nationals in 2012, according to the government.

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Beyond California, sunbelt states in general are attracting a lot of foreign attention these days. Post-housing-bust bargains in resort and retirement areas like Las Vegas and Naples, Fla. have have gotten buyers from Canada, for example.

Four states accounted for 58% of all foreign sales. Florida had 23%, California 17% and Arizona and Texas 9% each. New York, an international business center and immigration gateway, and Virginia, close to the Washington corridors of power, both came in at 3%.