In Beijing's vast network of unused air defence bunkers, a million people live in small, windowless rooms that rent for £30 to £50 a month, which is as much as the city's army of migrant labourers can afford.
"We have two sizes of room," he says, "The small ones [6ft by 9ft] are 300 yuan [£30] the big ones [15ft by 6ft] are 500 yuan."
"Our tenants are working in the wholesale market and peddlers selling vegetables or running sidewalk snack booths," he adds. "There are dozens of similar air defence basement projects in residential communities. In this area, they say 100,000 live underground."
### To buy a small flat (860 sq ft) it costs more than £200,000. In a city where the average monthly salary is 4,000 yuan, it would take 50 years to buy such an apartment, assuming they saved every penny they earned.
Vast discrepancies between house prices and earnings are creating social and economic difficulties for China's government – the poor can't find decent housing while the rich look to store their wealth in a speculative, bubble-prone property market.
With inflation and wage pressures mounting, growing number of investors are starting to question the sustainability of China's investment-heavy growth model. A survey of global investors by Bloomberg found 45% of them expect a financial crisis in China within five years, with another 40% anticipating a crisis after 2016.