An OC cannot legally prevent an owner from leasing their lot or lots to more than one person and any By-law that attempts to do so is invalid by virtue of Sect. 49 of the Act, as has been pointed out.
In the absence of any Local Government regulation, it follows therefore that an owner can rent out a garage to one person and the unit to another person.
As the Chairman and Secretary of an OC I don’t particularly like the situation due to the security aspect, but that is the law. No good going to the CTTT. They cannot override the Act.