GST doesn't apply to residential rent. You're not liable for GST on the rent you charge, and you can't claim any GST credits for associated expenses.
This applies even if you carry on another GST-registered enterprise. For example, if you're a ride-sourcing driver, you will need to account for GST on your ride-sourcing activity, but you don't need to account for GST from income earned from renting out a room or a house or unit. This is because GST doesn't apply to residential rent.
You have to pay GST if you provide accommodation in commercial residential premises, such as a hotel room or serviced apartment, a bed and breakfast, or if you rent out commercial spaces like a function room or office space. These types of accommodation are subject to GST.
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GST doesn't apply to residential rent, however you may need to report and pay GST if you provide accommodation services or rent out commercial spaces.