As Treasurer Joe Hockey continues to take flak over his advice for would-be homeowners, his own living arrangements have prompted calls for greater scrutiny of politicians' travel allowances.
Mr Hockey defended his use of travel allowances last year after a News Corp Australia article reported the treasurer had legally claimed more than $100,000 to rent a Canberra house from his wife.
Federal MPs are entitled to $271 a night to cover overnight stays in the nation's capital.
This week, Mr Hockey was under renewed pressure after he said the Sydney housing market is affordable and anyone hoping to get a foot in the door should start by getting "a good job that pays good money".
Independent senator Nick Xenophon on Wednesday said if taxpayer-funded allowances were being used to help pay off the mortgages of politicians and their families, more transparency was merited.
"I don't think it's unfair to require transparency, for that accommodation to be publicly made available," Senator Xenophon told ABC TV.
When the house or flat is eventually sold, information about whether the MP or their spouse made a capital gain should be made available.
The South Australian senator added: "I like the idea of a portion of that capital gain being put back into Treasury's coffers - although the flipside to that is that if the housing market crashes and the MP makes a loss, I don't think taxpayers would want to subsidise a bad investment decision by the MP."