I saw this yesterday morning outside my dentists office. A commercial tag for a commercial vehicle but I thought it a bit funny the tag said Commercial Truck...
I used both my Gen 2 and later my v as a cargo vehicle, with all the rear seats folded down. If your cargo does not weigh much, it is fine. (It has been 15 months, you may need to admit you are not a newbie)
We're in the process of moving and using our Prius v as an occasional cargo vehicle also... Only 11 months. I still don't know enough to not be a newbie...