I heard many years ago (pre-smart phones) about Canadians who cross regularly in RVs for the winter, bringing a literal binder of documents/photos showing they have a permanent home in Canada, pay taxes, have medical insurance paid up, proving they have a job to go back to, or are retired, the planned itinerary of RV parks, etc.
There was a reality TV show about the border I watched once - a dumb Canadian guy with his car full of clothes and TV, etc, wanting to drive down to stay with his girlfriend for a few months...nope, turned back.