Professional tenants (criminals) are very likely to show up with their own credit report and are usually slick enough to convince most landlords that they are the salt of the earth, reliable, upstanding socially conscientious and morally just to the point of being bitterly sweet.
Never trust, always insist on doing your own report.
Landlords need to understand that a free credit report that a individual gets on line does not contain the information a landlord requires nor can it be confirmed that it is even real. It often does not even contain the actual credit score itself let alone the records of creditors or the occurrences of 30, 60 and 90 day late. A individuals free credit score is useless.
Landlords need to be certain the credit report is not a forgery and applies to the individual in question. No legitimate business is going to provide any money, credit or service to a stranger that walks in off of the street with there own credit report in hand. Try getting a car or bank loan that way. We need to be professional about the operation of our business involving our asset worth hundreds of thousands of dollars being placed in the hands of strangers. Why should we care if a credit search causes a minor blip on a individuals credit report.
When dealing with a applicant refusing to provide a SIN tell them you insist on doing your own credit search. This way you will find out if the SIN is the issue or in fact it is a poor credit score that they fear. If you are not comfortable insisting on a SIN let it slide but insist on authorisation to do your own credit check. There is very little value in a "potentially good applicant" when compared to a bad tenant that can destroy your business.
We are either mom and pop or professional, take your pick.