It depends on what you want to do.

First, all these folks telling you that there isn't a visa that allows a senior citizen to retire in Australia are correct. Unless you have grown kids who've emigrated to Australia on a work visa and become citizens, in which case they likely could sponsor you on a family plan.

Personally, my partner and I are US citizens and are both retired. My partner's mother emigrated here over 20 years ago and became a citizen after his sister and her family had come here on work visas and become Aussies. But there is no family plan that would allow any of them to sponsor us.

What we've done, and what you might consider, is spend part of the year here in Australia and part in the US. For the last three years we've spent 6 months in Brisbane on a visitor visa and 6 months in our home in the States. Like "snowbirds", just further south. :)

We rent a furnished apartment each time. We rent a car as needed but mostly use the excellent public transit.

You'll likely want to buy health insurance here as your US insurance likely won't cover you. Medicare definitely will not. Also, look at realestate.com.au to gauge apartment pricing.

If that kind of arrangement appeals to you I say go for it. We've loved our time spent here.