What's your advice on which car to buy for towing a 21-foot caravan around Australia? I would like to spend around $40,000, but this may be hard as from my research it's either a LandCruiser or a Jeep Grand Cherokee, as we need a towing capacity of 3500kg.
You won't buy anything new for that sort of money; a used 2007 Landcruiser would still soak up all of your budget. Perhaps go for something like a used Ford F250; that would have all the towing capacity you need.