I had the same experience in one of the Dilawri dealer. In the purchase and sale agreement, there is no mileage, but when we got the car is over 600km.
We have to tell the manager give us a different car or will report to OMVIC for investigation. At the end, we received a new set of snow tires and a lot of free stuff since there is no other car available. Just a reminder note, the transmission broke very soon (about 8 months) and they have to replace.