Most of my experiences with renting cars abroad have occurred in either Germany, Austria, or Mexico. While these experiences have been vastly different from one another, a few key concepts remain true for each.
Get the Insurance
If you take one piece of knowledge from this article it is this, always get insurance when you rent a car. This applies to situations both domestic and abroad. The first time I rented a car I was heading to the mountains and had it not been for the rather treacherous terrain I probably would have foregone the insurance. Sure enough at the end of my trip a large amount of snow fell off a tree, and due to the extremely cold temperature and the force with which the snow fell, it cracked my windshield all the way across. I shudder when I think how much this mishap would have cost me (money, time, and stress) had I chosen to rent the car without insurance.
Pick the Right Automobile
This probably seems like a no-brainer, that is until you see a group of 5 tourist trying to squeeze themselves into a 2-door convertible. I know there is a temptation to rent a cool sports car or something more fun when you are on vacation, but think critically measure your wants with your needs. Picking the right type of transportation can go along with towards the overall happiness of your vacation. In my experience unless you are traveling very long distances, it is hard to go wrong with a van or an SUV.
The earlier out you start planning your trip, the earlier you can start thinking about what type of transportation you will need. This is important because the more you can shop around and the more you can learn beforehand the more you are going to be able to save.
When you are abroad it is important to remember you are easy to take advantage of, and renting a car is no exception. In my own travels, this seemed more likely to happen in countries like Mexico or the Bahamas in comparison to European countries. As for the reason why this is the case, I am unsure. The point is take your time and do plenty or research before you get there to make sure you are dealing with a reputable business.