I hear ya about land and property appreciation in Panama but I am not convinced. yes there is some appreciation but there are far more sellers than buyers; so if you have to shift gears and spend more time in canada or the US you can't just put a sign up ask for what you want and see it sell in a reasonable time. You have to give it away to sell it in a timely fashion.
There is no question that Panama is the most cost appealing value for money place to retire; but it is risk free if you lease. Really do you think your kids will have any interest in settling in Panama when you pass? Leasing gives you the best of both worlds and takes away the risk.