As long as the aircraft is “N” registered to a U.S. entity, Transport Canada is ok with your class of aircraft (privately owned & not a pressurised turbine/a non Part 604) staying in Canada. CAR 202.42 applies. There are companies in the U.S. ,Delaware especially, that specialise in Offshore ownership of “American” aircraft.
However, be very careful to ensure that Canada Customs agree with your assessment of what constitutes “importation”. There were a couple of N registered aircraft a few doors down from me in Alberta. The owners tried a scheme that sounds like your plan, did not pay taxes and the planes were seized after a few months while they were being painted and upgraded. They never flew after initial arrival. I understand the fines were equal to and on top of the taxes levied, and because the money ran out the planes went back to the states on a truck.
Cessna 172s have gotten stupid high priced because all the flying schools have been chewing them up.
PilotDARs comments are very true.
The purchase price of a machine is often inversely proportional to the operating cost. Cheap to buy, expensive to run or Expensive to buy, less expensive to run. The annual costs (fuel/maintenance/overhaul reserve of engines & props/insurance/etc) of a turbocharged light twin is likely to run a private owner 4 times what a 172 would. The hit if a major piece breaks is in another league as well - I would plan on $70,000 CAD to overhaul one Seneca engine against $35,000 CAD for the 172. Your points on the safety are spot on, but it ain’t a small increase in cost.