My 12 year old tug and 16 year old Aussie soft floor camper cost approx $19,000 all up.
Have probably spent another $5,000 on fridge, dual battery system, solar panels, rear fit out, etc.
$24,000 for a set up like mine is relatively cheap, but still need to have the discretionary income to afford it.
Certainly possible to get out there for far less than that if you cant afford it, and just add the extras slowly.
Apart from mud / sand / high country, there aren't too many places a regular car cant take a light camper trailer. People were doing it for years before the advent of modern 4x4 trucks, and roads were a lot worse then.
"Take it slowly" is possibly the best 'accessory' available, and it is FREE.