I'm not sure my STATE FARM Insurance would like anyone else driving my vehicles. Never asked that question before... Having the trailer insured both by my insurance company and your insurance company from Canada might not work either?
I would most definitely have both parties research what is needed and be legal upfront about everything... Lawsuits can get expensive especially when who is to blame for things.
Letting someone outside my family drive and have custody of my property on my Insurance sure doesn't sound like a good idea to me... All of my vehicles is in both my wife and myself names on the Titles.
Have no idea what the aspects of this is - have never asked before...
Roy Ken