Revenue Canada...
has something that is referred to as a lifestyle audit. Simply, if you are living beyond your stated income, you can be in deep trouble. They search all and, I do mean all your records. Your life is turned upside down. Assets can be taken, penalties assessed and possibly jail time (in extreme circumstances but, it does happen). It happened to a good client of mine. Thankfully, he had a good lawyer and only had to hand over several investment properties.
Moral of the story. Make sure a REASONABLE income is declared based on your lifestyle and keep detailed records to back it up.