I will not give you a list of the most popular car hire companies in South Africa because popularity and excellent service are not always synonymous. I will tell you what a good car hire agency should be able to do for you and then you can use that information to see whether any particular one meets those criteria.
If you are going to need the car for a period of more than two days then you should be able to get a company that should be able to offer you a cover charge for the period than the usual daily rates and charge per extra km. A longer lease should qualify for a bigger discount when calculated against the daily rate.
Another thing that you can find out about are the add on features that you might need. A good car rental agency will have roof racks for luggage and maybe sports equipment or extra storage facilities. Not for free of course I’m just saying they should have them available should you ever need them.
You should also find out about the terms and conditions of insurance in relation to extra drivers. Normally you would be required to register additional drivers at an extra cost but considering the length of your lease the car rental agency should allow you to have them simply registered and their details filed.
should be able to arrange your other requirements as well. That is book your flights, tours, cruises and so on. This will normally come at an extra cost to you of course. They should be able to tell you clearly the terms and conditions regarding your lease.
Most agencies will either not point out the penalties and conditions od breach of your contract. You should be clear as to what these are and how they affect you. Even though I will not list the popular ones I will just mention them quickly Hertz, Avis, Budget and RAV are just some of the more preferred car hire agencies in the country. If you want to access them and compare them all at once just look up any of these: