A title search may not be useful, as a young Anne Dunham would probably have been a renter.
Perhaps the city water billing records would show who was paying the bills in 1961.
If she filed a tax return, there should be some records there...dmv, voter registration, magazine subscriptions, etc are all places where a PI could try to bribe his way into getting access to information.
You are forgetting that Ann was back in WA state before the end of August, 1961 staying with a friend of her mother and didn’t return to HI until early 1963.
Quite right. The Honolulu Advertiser speculated last November that Bambi's parents resided in this cottage behind the house at 6085 Kalaniana'ole Highway: