While renting a car in another country comes with freedom from rigid bus/train schedules, it does come with it’s own set of complications. There are very harsh differences between the United States and other countries in terms of operating a vehicle - including rules of the road, car systems, insurance, and even blood alcohol level laws!
Figure out your insurance coverage. Rental insurance always seems to be one of those questions you don’t think about until you are standing at the counter in the airport terminal. However, abroad this becomes more than a nervously answered question. Make sure that you verify your coverage ahead of time. Typically your credit card or auto insurance at home is enough to cover you but we recommended getting the policy in writing to keep with you along your travels.
Tip: Ireland requires the supplemental insurance and can hit you with the extra fees while you are over there, so be sure to make room in the budget!
Consider getting an International Driving Permit. An International Driving Permit, or IDP, is the document, along with your home’s drivers license, that allows you to operate a vehicle abroad. Not all countries require you to have an IDP to rent a car, but some do so it is best to check with you rental agency beforehand. Also, keep in mind that variations can occur within the same continents. For example, Europe doesn't have the same regulations throughout- Greece requires an international drivers license to be obtained in advance, whereas Italy and France do not.
An IDP only costs about $20 and are valid for one year. To apply you must “be at least 18 to apply, carry BOTH your IDP and your valid driver's license when driving abroad, and obtain your IDP from the same country that issued your driver's license”. You can review how to apply HERE.
Make sure you reserve an automatic car in advance. Automatic cars are more frequent than not in the United States. However, cars abroad are more often manual so if you are unable to or uncomfortable operating a manual vehicle in a foreign country make sure that you specifically request a automatic car in advance!
Brush up on the rules of the road. Driving on the left side of the road may seem like one of the biggest considerations, but keep in mind that other countries have rules of the road that are less obvious to Americans. In some countries, for example, you can’t turn right on red. In others, the slow lane can’t be used for passing. Read up on what is customary in the country you are visiting before to avoid a surprise ticket.
Know your limit. Vacations often times mean indulgence. If you are looking to rent a car abroad, keep in mind that different countries have different laws about drinking and driving. For example, Hungary has a zero-tolerance policy while Italy’s limit is .5 grams per one liter of blood. So before heading out for that wine tasting tour or ordering that pint at lunch, know the limit at your destination.