I was recently towing my caravan back up through France and caught up with a British outfit that was doing the same thing.......I was able to have a good look at the other outfit and followed it for a while in traffic whilst traversing Rouen.....It was a brand new Mitsubishi 4x4 towing a brand new Swift twin axle.......an investment of around £60000.00 ...........Why weird logic?......The owner had spent all that money but apparently could not afford any towing mirrors!!!......when I was following I could not see his mirrors at all and he could not see me......His blind spots were large enough to hide a Truck!!