I don't have any experience in the matter but planning my own upcoming (2026, fingers crossed) trip I have done some reading and some sites recommends UTE / 4WD, but of course that's only if you are planning to do driving in more rural area 
Just thought to say because OP didn't specify if he is going to make drives in outback or not
So when you say you want to work your way down the coast from Cairns to Adelaide are you going via Melbourne or do you plan on turning inland at some point and cutting across to Adelaide?
In terms of a vehicle I would say overall Australia is far more car friendly than public transport supportive. If you only want to visit major cities than public transport would be effective but if your plan is to meander slowly hitting up small towns, isolated beaches, national parks or going bush/outback then you will need a private vehicle. As for what type, if you have no intention of sleeping in it than a minivan does seem like overkill and you would save a lot on petrol with a smaller, more economical vehicle.
[ Edit: Edited on 7 Nov 2022, 16:05 GMT by Teoni ]
Quoting hennaonthetrek
I don't have any experience in the matter but planning my own upcoming (2026, fingers crossed) trip I have done some reading and some sites recommends UTE / 4WD, but of course that's only if you are planning to do driving in more rural area
You only really need a 4WD if you plan on driving actual 4WD tracks, tracks that cross rivers, dirt roads in bad weather or going off road completely the latter which should only be attempted by experienced 4WDers and usually with a modified vehicle. Otherwise I would say about 90% of roads are 2WD accessible though as I alluded some roads will become 4WD only in rainy weather which is why when driving around Australia you should check state run road conditions websites and local council websites that will update you if a road becomes impassable.
Quoting Teoni
You only really need a 4WD if you plan on driving actual 4WD tracks, tracks that cross rivers, dirt roads in bad weather or going off road completely the latter which should only be attempted by experienced 4WDers and usually with a modified vehicle. Otherwise I would say about 90% of roads are 2WD accessible though as I alluded some roads will become 4WD only in rainy weather which is why when driving around Australia you should check state run road conditions websites and local council websites that will update you if a road becomes impassable.
That's actually really helpful, thank you! Sites that I have read so far haven't said this as clearly as you just did
(The dirt tracks / going off road- part has been clear but not that some "2WD roads" could become 4WD roads in a bad weather )
Australia is a fantastic destination for solo travel. As an Australian I couldn’t speak more highly!
Solo travel in Australia is incredibly safe but with any travel, preparation and research is key to ensuring a smooth trip.
Australia welcomes loads of travellers every year including backpackers so you’re guaranteed to meet others along the way. Many gap-year students and young traveller’s visit here to experience life down under before further study or getting a job.
There are plenty of hostels, hotels, and Airbnb’s, plus the majority of the population speaks English. If you prefer to travel with others, there are a range of solo travel companies and tour groups to explore such as Topdeck or Contiki.
Adelaide is spectacular, make sure to add kangaroo island to your bucket list or do a road trip along the peninsula and check out the insane pink lakes.
If you are driving across the country make sure you have plenty of supplies, a sim card and first aid kit. Australia is huge and the population in some areas such as Central Australia is very low. If you were to break down, get lost and lose reception you could find yourself in a bit of trouble.
Also plenty of bug spray and if you are going hiking, do your research on protective gear. Snakes, spiders and other native animals can be deadly. And sunscreen the UV is extreme here and you will get burnt very easily even as early as 7am!
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Olivia
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