Secure the property, change locks if needed, alert security company
Their home, and the security company or body corporate if there is one.
Some steps differ by region inside the country.
Where
Their home, and the security company or body corporate if there is one.
How
Collect all sets of keys and remotes, including any held by domestic staff, neighbours, or tenants.
Phone the armed response or security company to update the contact list and keypad codes.
Tell the body corporate or estate manager in writing who now holds access.
Photograph each room and any valuables before anything is moved. This protects you if the estate is later queried.
What to bring
Keys, alarm codes, and gate remotes
The death certificate or the DHA-1663 form
Timing
Same day where possible, certainly within the first week.
Sources
This is practical information, not legal, medical, or financial advice.