Housing
Housing seems to be the least likely of all the items you'd anticipate to find on the black market. To be honest, no one was importing homes and selling them off-the-books, but there were questionable practices in some places about rental costs.
During the war, many American employees moved north to Canada, which caused housing issues in towns like Edmonton where rural workers were also moving to seek employment. The maximum monthly rent was $25, and owners of rental units had to register them.
However, others who viewed the housing crisis as a chance to earn quick cash cheated the system. Some people ultimately paid $10 per month to live in a garage, while others paid up to $40 or $50. When it eventually reached $100 or more, home sales surpassed 300% of the rates that were set by law.