Before purchasing a used mobile device, we request that you check to see if the device has been reported lost or stolen by visiting the Canadian Blacklist here
Before meeting a seller in person, request the 15 digit IMEI and check the status of the device by using the link above. If you then decide to examine the device in person, please make sure the number you were provided is the same on the actual device. Devices that are reported as lost or stolen on the National Blacklist will not operate.
Here is more information about unlocked cellphones