In the normal course of business, bartering occurs. It is important to carefully approach this as the tax laws are strict. Basically, one should include the regular normal income as revenue and the cost of the barter as an expense.
For example, let’s say John rents a basement apartment for $600 a month to Stuart. John and Stuart agree to cut the rent by $100 a month for snow removal, and lawn maintenance. It is a net of $500 income for John. The CRA wants to see the $600 and $100 figures in the income and expense areas, respectively.
For more information: http://www.cra-arc.gc.ca/E/pub/tp/it490/README.html