It is not possible at this time for a foreigner to rent and drive their own automobile in Vietnam. It is possible to rent a motorbike for a very reasonable amount of money. Taxis or taxi motorbikes are the norm in Vietnam for visitors while it is also possible for long term visitors living full time in Vietnam to obtain a Vietnamese drivers license and own their own vehicle. Public transportation abounds and is available in all price levels from non-airconditioned and older buses to high quality and high comfort travel vans (you will pay a fair price for these). Depending on your individual circumstances a combination of having a rental motorbike in conjunction with taking inexpensive taxis or motor bike taxis might be the best route until you learn the ropes so to speak. There are also the legendary Cyclos which can be seen almost everywhere but in recent years the laws have unfortunately been weighing against this form of transportation with entire neighborhoods being declared off limits to them. By all means take a ride in one of these for a real trip back in time and if you take your time in explaining your interests to your driver you may have a tour guide who will show you a most memorable drive through the historic areas of many places, especially in Saigon.