Thanks Jimmy for this sage advice.
This is an issue our building has also had to deal with.
We used many of your suggestions to make ‘doing business’ as difficult as possible. First step was by the strata manager requesting a copy of the lease agreement (as required by the Strata Act) from the managing agent. The name on the lease (male) did not match up with any of the actual residents (all female), as cross referenced to who was using the building’s security access. This meant that the person who had been allocated building security access was no longer a resident, this entitled us to turn off all building access, consistent with our by-laws. We then worked very closely with the apartments managing agent who agreed with us that the apartment had been ‘sublet’ and then took action through the then CTTT, with our full support. Eventually the agent was able to change the locks.
This would not work in all instances, as it is reliant on the property being tenanted, and the leasee not in residence. I also can not speak highly enough of the managing agent involved here as well.