Hi and welcome
500, Panda, Punto are all those things, in Europe at least. Then it comes down to personal preference.
My Panda puts a smile on my face, very well built, bomb-proof FIRE engine, and over the 6 years I've had it I don't think anything could have been cheaper.
As Anthony says, parts scarcity in Oz might push up cost of servicing, repairs, insurance.
As mentioned 500, Panda and Punto are all nice cars, good to drive and cheap to run.
I used to live in Australia, the price of cars is fantastical compared to the UK. I assumed that was something to do with all cars having to be shipped in thousands of miles, and a small domestic market. If you're going to buy an older car then check over the service history carefully.
When considering my Panda, alternatives were Mazda2, Suzuki Swift, Toyota Yaris. All smol cheap fun
Probably not as cheap as Fiat here, but maybe cheaper where you are?