If the car passes your inspection and test drive here are a few more things to bear in mind before making an offer:-
Every car in South Africa has to be registered with the traffic authorities, and before transfer of registration can take place the car must go through a roadworthy test.
If the car is offered with a certificate of Roadworthiness, ensure the certificate is current.
Ask to see service and repair history and well as repair receipts. Treat a denial that these receipts exist with suspicion.
Check that the distance shown on the odometer tallies with service and repair receipts.
Check that the car's registration and chassis number matches those on the registration document.
If the vendor is not the person named on the registration document ask for written confirmation from the registered owner that the vendor is authorised to sell the vehicle on his behalf.
Ask if it is permissible to have the car inspected by an independent mechanic or the Automobile Assocaition.
If it is (and you can afford the added expense) ask the mechanic to carry out a cylinder compression test to assess the condition of the engine and also to estimate the cost of any repairs he thinks may be warranted.
You can then ask for the cost of these repairs to be deducted from the asking price.
If you have a car to trade in don't mention the fact until you have negotiated a discount for the one you want to buy.
If you are buying from a trader, depending on the value of the car, it may be worth investing in a warranty. Read the warranty small print very carefully as some warranties exclude more than they cover.