You can tax a 4x4 either as private or commercial, private is dearer for tax but then insuring it privately is cheaper, check out the costs and weigh it up. Also I had a lot of trouble getting commercial insurance (the dearer one) for my dad on his jeep thus year, Icwas surprised at how many companies would not quote because he is not 'actradesman carrying tools' - nuts, he's a vet, so much less risk to an ins co. I would have thought than someone carrying expensive tools...