If you are registered for GST/HST and use vehicles for commercial purposes you’re required to collect GST/HST on the sale of the vehicle.
For individuals or partnerships registered for GST/HST purposes.
GST/HST must be collected on the trade-in value of any passenger vehicle used 90% or more for commercial purposes. GST/HST must also be collected on the trade-in value of any motor vehicle (not just passenger) used 50% or more for commercial activities.
For Corporations registered for GST/HST purposes.
GST must be collected on the trade-in value of any passenger or motor vehicle used 50% or more for commercial purposes.
In the above cases, both the customer and the dealer involved in the transaction may claim their respective Input Tax Credits (ITC).