Rules vary province to province, and provider to provider - so without knowing where you're based out of, I don't think anyone can really comment...
That said - when I got insurance for my trailer (way cheaper then your MH, for full disclosure), RBC was cheapest, because they have my house and auto already; Wayfarer was next... That's in Ontario.
2014 Grey Wolf 28BH, behind a 2015 F350 Diesel Crew Cab
Nights Camped 2016: 44
Nights Booked 2017: 11
Nights Camped 2017: 6