Hi there,
For all the replies above and mine, it's definitely easiest with a right-hand drive.
Where do you plan to start your trip?
Personally, I bought a 4x4 in Namibia with a tourist visa, and a car in South Africa with a 3-month work visa.
I also bought vehicles in Angola with left-hand drive, but I had a work visa, and it was my company’s logistics guy who handled the paperwork.
Without living there, I wouldn’t recommend it.
Administratively, the system is similar in South Africa and Namibia:
First, you need a document, the "TRN" (which isn’t the same in South Africa and Namibia), from the "road authority" (Namibia) or "department of transports" (South Africa).
Once you have this document and found a vehicle, the process is quite similar to France before the computerized system:
the seller gives you a document, and you submit it to the authorities.
Compared to France, it’s cheap.
https://www.gov.za/services/driving-licence-driving/apply-traffic-register-numberFor Namibia, I went through an agent who handled everything for me, and I picked up the car when I arrived.
For South Africa, I did everything myself, but not in a big city.
On the "Français du Cap" Facebook forum, some people struggle to get the TRN in Cape Town.
As for the condition of the vehicle, I can confirm that even in reputable garages in South Africa, some can be shady...