Looking to make money in the fastest-growing Australian housing markets of Sydney and Melbourne? You've probably got one year to lock in gains of up to 16 percent, and after that — well it depends mostly on the government.
That's according to forecaster Louis Christopher from SQM Research, who told CNBC's "Street Signs" that there are a few triggers that could force a correction.
"I think, roughly, we would need to see a 50 to 100 basis point increase in interest rates: That would be enough to create a correction in the marketplace by the order of maybe some 5 percent for the first year. Now the risk is that if we see the [Reserve Bank of Australia] lift by that amount over the next two years, and [Australian Prudential Regulation Authority] step in the market rather aggressively, that's when you could see potentially a far larger correction in Sydney and Melbourne."
And that's just Sydney and Melbourne. As for Perth and Darwin, you won't make any money this year if Christopher is right, with house prices predicted to fall as much as 9 percent this year before a slow recovery.
"We did also say that this is likely to be the last year of the falls and I think there is some evidence starting to play through now in the form of rental vacancy rates, which are topping in those cities, which suggest that the bottom is coming," he said.
Christopher has a track record of being right, and has been in the property forecasting business for 16 years. In fact, the Australian Financial Review has named SQM the most accurate housing market forecaster for the last two years.
This year's growth is mostly driven by low interest rates, population growth and a strong economy — assuming there are no changes to the cash rate. And Australia's central bank is another reason to pay attention to Christopher: The minutes of its March meeting included a warning on the housing market, and pointed to a buildup of risks.
"Borrowing for housing by investors had picked up over recent months and growth in household debt had been faster than that in household income," the RBA minutes said.
Even so, it's unlikely that higher interest rates will come this year, as the central bank is between a rock and a hard place. While they are concerned about housing, growth in some parts of the economy is still sub-par, and the Aussie dollar may be too strong for the RBA's comfort.
Added to that, the banks are doing the RBA's job for them, with all four major banks hiking rates in the past week. CommSec's Craig James said that this is already having an impact: "Anecdotal evidence is that investor demand has weakened markedly in response to rate hikes."
This leaves the government holding the pin that could burst the bubble. We know that regulators are looking at new ways to slow bank lending, and rumors are this will involve cracking down on interest-only loans, and demanding buyers stump up more equity when buying a home.
"Any aggressive action by the regulatory bodies could create the trigger for a new downturn and we now think the probabilities are increasing they may well take action prior to June," Christopher said.
But it's not all doom and gloom. Bank of Queensland CEO Jon Sutton told CNBC that he is not worried about a hard landing.
"We've seen significant price increases in housing in both Sydney and Melbourne. However, I think a lot of that is to do around supply and bringing more supply on, will actually moderate those sort of house prices in those key markets."
May 9 is the next date to watch out for — the day of the federal budget — as it's then the coalition is likely to announce any measure to address the overheated parts of the market.