A supply of booth space together with chairs and tables to exhibitors by a registered charity hosting a conference relating to its objects was deemed in light of s. 138 to be a single supply of real estate which was exempt, given "that the provision of the tables and chairs does not materially affect the amount of consideration charged." CRA stated:
we consider a supply to be incidental to a particular supply if the supplier's primary objective is to provide the particular supply, and if the consideration would be the same or only marginally different if only the particular supply were made.