The chances of prices falling is slim but not nil & here's my two cents.

Sellers control the list price based on education, markets stats, & professional advice of  their REALTOR® etc. Buyers ultimately dicatate how much a home will sell for. The more buyers interested in a property listed for sale the higher the selling price.  If there aren't any buyers submitting offers it is a clear indication that the list price is too high or it could be something unrelated to the price like the property isn't move-in ready, requiring expensive & time consuming upgrades that most buyers don't have the patience for nowadays to hire a contractor to renovate to suit their own tastes post purchase. Whatever the problem might be it will require the property to sit idle (aka go stale) waiting for the right buyer to come along & submit an offer. Until the seller is motivated to adjust the list price will the price fall. 

Another possibility & again unlikely but very well could happen is a recession or depression. Most people are house poor these days living pay cheque to pay cheque as housing takes a greater percentage out of peoples wages than it use to.  Loss of employment is the highest probabability nowadays to start the ripple effect of falling house prices. As we're seeing in certain parts of the country specifically in the province of Alberta, the Oil & Energy sector has taken a hit causing undue hardship on many Albertan's which has already had negative effects on the Calgary housing market. The Bank of Canada continues to increase interests rates for no apparent reason other than corporate greed, squeezing every last dollar out of Canadians. Oshawa, ON was recently educated that the cities main employer GM was moving operations to Mexico. So far GM's departure from Oshawa, ON will cost the city thousands of jobs, a large tax base that will have to be made up else where by the residents & corproations that call Oshawa home in order for the city to maintain operations & not become insolvent like Detroit, MI. Hopefully if rumours take reality, Tesla Motors will plant roots & save the day...fingers crossed for Oshawa. 

Sobeit that a city or government becomes insolvent the collapse would occur instages. City would put leins on real estate & sell to public to make ends meet. Investors cash would need to dry up before they just give a deed away. More than likely properties would be abandoned & people would jump ship to the next employment source wherever that maybe depending on the grand scheme of things. What would happen in the interim of such a collapse people would downsize to rooming housings as shelter until living on the street was the only option.

So anything is possible but it would be a while before prices fall to rock bottom prices. If you're sitting on the fence about buying, today is the best day to buy real estate not tomorrow or the next day. You buy to make money, not sell. If you make money when you sell that is a bonus. Since the Liberal Government applied stress test qualifications on Canadian Jan. 2018 If you can come up with the 20% downpayment, & can manage the monthly mortgage payments comfortably... what are you waiting for?  If you're like most Canadians & don't have the required downpayment but have some savings look at markets where you could qualify to purchase real estate as an investor or network & find like minded investors to discuss investment opportunities. Rents have SKYROCKETED 12% from this time last year & climbing rapidly. If you want real estate prices to fall as quickly as tomorrow all that needs to be done is DEMAND from your city council that they: 

reduce the tax rate on privately-created buildings and increase the tax rate on land. The lower tax rate on buildings makes them cheaper to build, improve and maintain. The higher tax rate on land reduces the profits from land speculation, which keeps land prices more affordable.  Further, revenue from taxes on land can serve public purposes, making public infrastructure more financially self-sustaining.to update the tax rates. This split-rate property tax, also known as “value-capture,” is already in use in a variety of cities around the world, including in high-density, high-population cities like Hong Kong, and in smaller cities such as Harrisburg, Pennsylvania. 

Source: Rick Rybeck

Next while you have city councils attention for shits & giggles, DEMAND they update the city land use policies to include the missing middle housing types. Most land use policies exclude these housing types to keep the riff-raff out. Sadly most city by-laws include unnecessary parking requirements as a way disguising it. When city council tells you they're simply following direction from the Provincial Government & the "Places to grow" lesiglation it's time to get your local MPP's involved. More than likely they won't do anything they don't have the authorization to stir up the status quo so you'll need to address this issue to the prime minister.

Governments are scared of upsetting homeowning electorates by introducing taxes that push prices down and they also know that permanently lower house prices would be a nightmare for the overexposed banks of the west. 

Source: Financial Times

What will your next step be? Are you serious to make change happen? If so, make this go viral for the better sake of humanity otherwise do yourself a favour & go buy some personal lubricant...it hurt less.