The key to China’s economic progress will be the rapid growth of the country’s middle class. In a research finding, Credit Suisse predicted that the household wealth in the country will double to $35.0 trillion by around 2015, based on achieving sustainable GDP growth at or near the current growth rate.

The economic analysis is simple; the extra renminbi mean more cash to spend on non-essential goods and services. This includes furniture, real estate, vehicles, and travel. The mobile phone market is staggering at nearly 900 million users, which I discussed in “China’s Mobile Sector Still Sizzling.”

An area in China that I continue to believe has tremendous long-term potential is the auto sector, but the short term will pose hurdles.

I have been a big supporter of the Chinese auto sector, but sales have been slowing as the government eliminated credits for fuel-efficient cars in 2011 and, in trying to ease the traffic congestion on Chinese highways, set a quota on vehicles sold.

The slowing is quite evident. In the first quarter of 2012, auto sales fell 1.2% in China. In the 11 months to November 2011, auto sales increased a trepid 2.6% year-over-year to 16.8 million units, down from a staggering 30.0% and 50.0% growth in 2010 and 2009, respectively, according to the China Association of Automobile Manufacturers (CAAM). The growth in 2011 is the lowest since 1999 and clearly poses issues for carmakers.

Yet there are some positives for the foreign carmakers operating in China. Sales of foreign vehicles continue to top the charts, while the domestic brands fell 2.3% for the first 11 months of 2011, representing only around 33.0% of total sales in the period.

You don’t have to tell General Motors Company (NYSE/GM) to go to China and look for growth opportunities. The company has three of its vehicles on the top-10 list for best-selling cars in China, including the “Buick Excelle” as the top seller and the “Chevrolet Sail” in number two.

The other top 10 are all foreign carmakers with the exception of Chinese BYD Auto Co., with its “Great Wall Haval” in tenth position.

The world’s automakers know that to grow, you need to have a presence in China’s auto sector, whether in a venture with a Chinese company or as a standalone manufacturer of vehicles. The auto sector is currently in flux, but companies need to be there.

Foreign cars are viewed as top-quality products in China, which is not a surprise given the widely known quality issue of domestic Chinese vehicles.

Can you imagine GM is known as a quality brand in China?

As well, GM is the top auto seller in China. GM and its Chinese partners sold a record 2.5 million vehicles in 2011, well above its U.S. sales. The “Buick” brand was tops for GM at 645,537 vehicles, up 17.4% year-over-year. Its “Excelle” brand sold a record 253,514 units.

GM is focusing its growth in China as it feels the steady rise in the middle class will drive the demand for cars. The automaker announced plans to invest a minimum of $5.0 billion in China in an effort to reach a sales target of five million vehicles by 2015.

There is clearly some slowing in the Chinese auto market, but I view dips as an opportunity to buy for those with a longer-term view.

There are numerous ways to play the Chinese auto sector. You can buy an auto company with exposure to China, such as the major global automakers. Alternatively, you can buy Chinese auto-parts makers. Some Chinese auto plays to take a look at include China Automotive Systems, Inc. (NASDAQ/CAAS) and SORL Auto Parts, Inc. (NASDAQ/SORL).