Yes my idea is to use a quad, so far it looks possible.
I've just recievedthis from the transport dept in SA.
In terms of the NRTA (Act 93 of 1996 as amended), a quadrucycle is referred to as: "motor quadrucycle" which means a motor vehicle, other than a tractor, which has four wheels and which is designed to be driven by the type of controls usually fitted to a motor cycle. All motor vehicles are liable for registration (Regulation 3) and licensing(Regulation 18) apart from those exempted under Regulation 5 (long list). Quadrucycles are not amongst this list. The MEC may charge a "flat rate" for vehicles not used on "a public road". Crossing a road / driving down a road (less than 1 km) is seen as not using a private road. The shoulder of a road (gravel section) is still part of a public road. Quads were not designed for "normal" transport on roads - so all the necessary requirements will have to be met (lighting, mirrors, brakes, tyres, reflectors) before it can be registered for public road usage.