Part of the problem is how difficult it is to understand what your obligations are, even if you intend to comply. And then there are things that are just plain unfair.  Let&#x27;s say that you live in Canada and you bought your house for $500,000 Cdn.  Five years later you sell it for the same $500,000.  Except during that time, due to exchange rate fluctuation, the house increased in value relative to the US dollar, going from, for example, $400K to $600K US.  (Entirely possible, given how much change there has been in the two currencies over the last few years.)  The US considers you to have made $200K US in speculation and expects you to pay taxes to the US on that gain.  Even though there was no gain -- you live in Canada and bought and sold the house in Canadian dollars. Capital gains exemptions don&#x27;t apply here--they consider this to be currency speculation.  Mindboggling.  And easy to get yourself in trouble over without realizing.