As you can see, this is very common. You'll have to check with specific States since some require a Driver's Licence to register a vehicle so you have to be a resident but most will let you do it (In the past, I've registered vehicles in VT and FL in my name and in SD using Americas Mailbox). Montana LLC is an option but you do have research that since some states are cracking down on abuse and it's a red flag (although as a non-US resident you'd probably be fine in any state). As far as the taxes, again, each state is different so you'll have to research the one where you plan on registering it. Insurance can be a bit more difficult since you won't have a US DL but you just need to keep calling around and you'll find a company (many will tell you they can't insure you if you don't have a US DL and US driving history, others will tell you they can't insure an RV unless they insure you're primary vehicle (which is likely registered and insured in Canada so not an option) but in my experience, you'll always be able to find a company that will sell you insurance.
One thing to keep in mind is that as a Canadian Citizen, you will likely not be able to bring the US trailer into Canada even for short periods of time without importing it into Canada (e.g. you can't leave it in US / Mexico for 11 months of the year and then bring it into Canada for 2 weeks during the summer). You probably also wouldn't even be able to enter it onto Canada on the way to Alaska without importing it.
