A quarter of Chinese buying property overseas leave their apartments vacant and the majority pay for their purchase with cash, a survey of mainland Chinese customers by investment bank UBS shows.

Another 25 per cent of overseas property owners use their home on a temporary basis, suggesting about half of the overseas properties owned by mainland Chinese were not fully utilised, the bi-annual survey suggests.

Overseas investment in Australia's housing market has stirred political sensitivities amid concerns offshore buyers are helping fuel Australia's property boom and are leaving homes empty during a housing affordability crisis.

House prices in the nation's capital cities have surged almost 44 per cent since 2012, according to the Australian Bureau of Statistics.