You are getting some bad legal advice by a Canadian that has NO bearing in truth for the US. If a state says that you must have brakes on ANY trailer over 1500# or above, then I do NOT care what or how your trailer was delivered, you can and in most cases will, be cited for improper equipment. Also, if you travel from one state that says brakes on 3000# into a state that says brakes on 1500#, you do not have reciprocity and MUST comply with the state you are operating in at that time. Reciprocity ONLY exist on drivers license, vehicle registrations and insurance coverage, period. ALL vehicle equipment is IAW the laws of the state you are driving in, NOT your home state.
That is why I tell folks, make sure your trailer has brakes on at least 1 axle, if the weight exceeds 1500#.