It totally depends on the country you are going to.

:-: In several countries in Central or South America it is cheaper, or approximately the same cost, to hire a car and driver than it is to rent from Avis. While the cost of a car and driver will actually be about the same, or even a tiny bit more than Avis alone (depending on the car class of course), with a car and driver the cost of the fuel will be included, and there will not be any "extra" taxes (regular rental tax of course) such as passenger facility charges, where with Avis the cost of the fuel will be over and above the cost of the rental, and there will be "extra taxes." This certainly applies in Ecuador, Bolivia, Paraguay, Suriname, Guyana, and French Guiana in South America, and sometimes Chile too. In Central America it often applies in Belize and Honduras, and sometimes other countries too. Also, in some countries, it is actually recommended to use a car and driver, and NOT to rent, for safety purposes, such as in Venezuela, although in VZ it is not generally cheaper, and the driver often will carry a gun.