MTR Corp, the city's government-owned railway operator, is also re-tendering a site atop a train station on which 2,900 homes can be built. The price was cut to HK$10.4 billion, 18 percent lower than two years ago, according to the South China Morning Post. The first tender in 2012 was withdrawn due to low bids.

While prices of some suburban land may fall as more sites are released for sale, prices in urban areas will remain steady as supply is limited, according to Simon Lo, head of Asia research and advisory at realtor Colliers International.

"Now developers are looking for high-quality sites in urban areas where they can be sure to attract homebuyers," said Lo.

Cheung Kong, which has not bought land since 2012, has about five to six years of reserves and may need to replenish soon as it sped up home sales this year, said Patrick Wong, an analyst at BNP in Hong Kong. Sino and Henderson both have about three to four years' worth of land in reserve, he said.

Henderson, controlled by billionaire Lee Shau-kee, is paying HK$4.7 billion for a site in the prime retail district of Tsim Sha Tsui, 38 percent higher than the median estimate compiled by Bloomberg. The company is planning to invest a total of HK$6.5 billion to build a shopping complex on the site that is currently an abandoned parking garage.

Sino is working with Chinese Estates Holdings Ltd on a redevelopment project in Kwun Tong district, an industrial zone in eastern Hong Kong where old factory buildings are being replaced with new commercial towers. The project is targeted to provide 1,700 residential units, according to the Urban Renewal Authority.

The price, which was not disclosed, is estimated to be HK$6 billion to HK$6.5 billion and is Sino's largest land purchase in five years, according to a report this month by Jonas Kan, an analyst at Daiwa Securities Group Inc.

Shares of developers have performed better than the market as a whole, driven by a rebound in home sales. The subindex of nine property companies rose 10 percent this year, compared with the 3.9 percent gain in the benchmark Hang Seng Index.

Henderson and Sino are among the top 10 best-performing shares in the Hang Seng Index this year. Henderson is the top performer in the index, with its shares up 39 percent. Sino has risen 23 percent and Cheung Kong has gained 12 percent.

The rally has boosted the wealth of the property tycoons. Cheung Kong's Li, whose diverse companies' businesses include property, infrastructure and retail, is the richest man in Asia with a net worth of $31.6 billion, according to the Bloomberg Billionaires Index. Sino's Ng has a net worth of $5.3 billion, while Henderson's Lee is Asia's second-richest person with a net worth of $25.5 billion.

Developers have accelerated sales and offered discounts to lure buyers after the government imposed three rounds of taxes to thwart a housing bubble. The HK$150 billion of new homes they are expected to sell this year compares with a five-year low of $92.2 billion sold in 2013, according to Centaline Property Agency Ltd, the city's biggest closely held realtor.

Ways to promote real estate sales	Mortgage rule changes said to be in the pipeline