While housing prices in China's megacities like Beijing and Shanghai remain sky-high, a little-known border city in the nation's northeast has developed a reputation overnight on social media for its extraordinarily cheap apartments.

A 50-square-meter flat costs an estimated 20,000 yuan, less than 3,000 U.S. dollars. Fan Huixue is one of those selling his property at such a bargain. He told us that he got two new apartments after his old hut was demolished. As one of them is now vacant, he decided to sell it soon to pay for his children's tuition rather than spending more on decorating it.

Zhou Zhigang, deputy director of Hegang's Affordable Housing Service Center, said many like Fan have been relocated to new flats since the city rolled out renovations of its shantytowns. Some with more than one flats tend to sell the unwanted ones at mere market prices. Zhou added that the relocation project enables residents to move into new apartments at almost no cost. "A great many of these affordable homes somewhat reduce the demand and price of commercial residential housing," Zhou explained.

Average home prices in the city's real estate market suggests that extremely cheap homes seem to be exceptional cases. Most houses for sale cost over 2,000 yuan per square meter, which is about 300 U.S. dollars -- much more than the anecdotal low price. But the average housing price here in Hegang is still rather low. Namely, it's quite common to find a 50-square-meter apartment worth about 15,000 U.S. dollars in Hegang, which may not be enough to buy even one square meter in downtown Beijing.

Locals have also seen a gradual cooling of Hegang's housing market. Wang Delong, a realtor at a local housing agency, said property trading volume has been declining in recent years. "Housing prices used to be stable but have dropped this year. I think a dwindling population has led to falling demand and price," Wang speculated.

Liu Lei, director of Hegang's Development and Reform Commission, believed that a transformation of the city will boost its real estate sector. Liu said Hegang lost its luster after the longtime coal-mining sector became sluggish, which lead to an outflow of talent, a decrease in consumption and downward housing prices.

Experts say Hegang is a microcosm of northeastern China's rust belt, which now faces the dual problem of an obsolete industry and resource depletion. While home prices in nearly all 70 major Chinese cities edged up two years after Beijing's restrictive policy to curb overheated housing markets, cities like Hegang are looking to end the plunging trend -- a sign of their long-awaited urban renewal.

"Building industrial clusters of coal, graphite, cultural tourism and pollution-free food will attract more people to Hegang and increase demand for living and working space," said Liu.