Title deeds
Check with the state/territory land titles office and the mortgage lender; transfers usually need probate
Some steps differ by region inside the country.
Where
The land titles office in each state or territory, or the mortgage lender if the property is financed. A conveyancer can run the search.
How
Order a title search from the relevant state or territory land titles office, or ask a conveyancer to do it.
Check whether the title is held solely, as joint tenants, or as tenants in common, since this determines what happens on death.
Contact the lender if there is a mortgage, and ask whether it carried any insurance that repays it.
Search in every state where they might have owned property, including holiday homes and inherited land.
What to bring
A certified copy of the death certificate
The grant of probate
The property address or title reference
Sources
This is practical information, not legal, medical, or financial advice.