When we went to Alaska, we checked with our insurance agent (State Farm), and they got me an insurance certificate that our insurance covered the MH and our towcar in Canada. As for personal papers, we had passports. I believe that birth certificates are also satisfactory.
You will be asked about firearms. They cannot be carried across the border. There is also a limit the amount of liquor that you carry across the border.
Hope this helps.
W8RLM - Bob
2006 Winnebago Journey, Model 39K, 2013 Dodge Dart