Generally, services from a real estate agent who is registered for the GST/HST related to the selling or renting of real property will be taxable even when the real property in question is exempt from GST/HST.
The real estate agent who is registered for the GST/HST has to charge and remit GST/HST on his/her commission and other services (other than financial services) provided to their clients. In turn, the clients may be able to claim an input tax credit to recover the GST/HST they paid for the agent's services if the real property is used in commercial activities.