BEIJING -- Six weeks until year end and city governments in China are struggling to meet their goal of preventing house prices from rising too quickly.

Statistics and experts agree that their chances of success are slim.

Guangzhou in south China is a megacity which has just rolled out detailed rules to slow house price inflation, including raising down payments on second homes. Beijing, Shanghai and Shenzhen all raised the threshold to 70 percent recently. These four cities have also restricted unregistered residents from buying apartments, but the rules have not yet yielded fruit as expected.

Of a statistical pool of 70 major cities, 65 saw month-on-month rises in new home prices in October, and 62 reported price gains in existing and second-hand homes, according to the National Bureau of Statistics.

First-tier cities continued to lead rises, with the prices of new homes in Beijing and Shanghai over 20 percent higher than a year ago, said NBS.

Short-term curbs vs long-term mechanism

The rules have a limited stabilizing effect on commercial housing prices because they are short-term policies.

By the end of the year, housing projects that sell for more than 40,000 yuan ($6,564) per square meter are not allowed for advance sale, according to Beijing municipal commission for housing and urban-rural development.

"I waited two months to buy an apartment in Daxing District outside the fifth ring, but the project's presale application was denied by the government," said Chen, a Beijing resident. "I don't think the prices will go down anyway if the presale is postponed till next year."

Regulations to curb demand may put a brake on prices for the rest of the year but their effects won't last long, said Chen Guoqiang, deputy head of the China Real Estate Society.

In Shanghai, only 20 percent of current home loans have gone to people purchasing a second home, according to Gu Mingde, deputy director of investigation and research at Shanghai head office of the People's Bank of China. Raising down payments for second-home purchases only affected a small group of people.

If the rules were carried out only to meet the yearly goal, they may further add to supply and demand contradiction, said Ma Guangyuan, an economist.

Industry insiders have noticed that purchasers have been holding back to see if prices drop after the regulations take force, and wonder how long will take for purchasers to start buying again and a new round of price rises.

The market is in urgent need of a long-term mechanism that will allow market to adjust by itself, said Zhang Dawei, director of Centaline Property's research center.

Managing supply-demand contradictions

While previous regulations to restrain demand have been effective, policy needs to focus more on the supply side to ease the supply-demand contradiction.