The traffic in Buenos Aires is fairly stressful so driving by yourself is not recommended. Walking or public transport is generally better for your blood pressure and fitness. If you know the area and want some adventure however, there are several car rental places that are easy to access.
An international driver's license is required, but if you have your driving license from your home country, you should be fine. The license must be carried with you at all times while driving. If you own the car you are driving, proof of vehicle ownership, insurance and receipt for last tax payment must also be carried with you. This is of course, not required with a rental car.
Almost all cars have manual transmission in Argentina, so being able to drive a manual is necessary. About US$80 a day is what you should be expecting to pay for a rental car, but with some searching, you can find cheaper prices.
Address: Olga Cossettini 1650
Primer Mundo :
Address: Av. Livertador 6553
Avis Rent-a-car :
Phone: 4480-9387 for Ezeiza Intl. Airport, 4776-3003 for Jorge Newberry Airport
Address: Posadas 1452
Dietrich Rent-a-car :
Address: La Recova - Cerrito 1575