1. Needs to be registered and have a trailer plate, (they are permanent, so only have to do it once), plus insurance which is dead cheap.
2. Don't buy one of the ones that is bolted together at the store, go to a reputable trailer place like FOT (
https://fot.ca/) and buy one made in Canada that is all welded together at the factory.
3. What Lubicon said and also don't buy a cheap trailer. We had a quality Canada Trailers 5x10 and towed tons back and forth past Fernie with zero issues of swaying or other.