A Traffic Register Number is required for anyone in South Africa who wishes to buy or sell a vehicle in their own name, if they do not have a valid South African Identity Book (ID) with a 13 digit ID number. It is also required for personalised number plates or registering a vehicle in the name of a business.
Beware, however, that this is a long process – up to a month – and the website does not contain up to date information. It is advisable to contact your local testing station to determine which one you should attend, and what documentation is required.
The latest information I was given included a long list of paperwork, my wife’s payslips, proof of earnings, proof you have purchased the car already, etc. In the end I didn’t bother and will just wait for my green ID book and permanent residency !