A re-elected Conservative government would spend half a million dollars next year to figure out just how many foreign investors have eaten up condos and homes across Canada, many of them sitting empty year-round.

The spending Stephen Harper promised at an event in Vancouver could ultimately lead to strict rules about what kinds of homes -- existing or new -- foreign investors are allowed to own.

Campaign material provided by the Conservatives pointed to rules in other countries that force foreign investors to only purchase homes under construction, or to limit home ownership for foreign nationals to just the time that they live in the country.

About 15 per cent of the condo market in Vancouver sits empty year-round by some estimates, with the owners sitting on the properties hoping to make a profit as the prices of homes rise.

There is also speculation that investors are driving up the cost of housing in Vancouver, raising concerns of a housing bubble in Canada's hot housing market.

Harper also promised to raise the amount first-time home buyers can take out of their registered retirement savings plans for a down payment -- 35-thousand from the current 25-thousand-dollar limit.

The Conservatives say that promise will cost the federal government an extra 30-million dollars per year in lost taxes starting in the 2017-18 fiscal year.