Step1
The first step to take to rent a car in Europe, specifically Germany, is to find a rental car company that will rent a car in Germany. Try Kemwel (resources below), who finds you a great rate with a local rental company to rent a car in Germany, such as Avis or Hertz. Type "rental car Germany" into your search engine on the internet to find such companies as Kemwel.
Step2
Contact the rental car company directly by phone. This way you can ask for the cheapest car rental rates available, and have your questions answered. You can reserve the car rental with a credit card.
Step3
The first question to ask is whether or not you need an international driver's license for your car rental in Germany. Some rental car companies in Europe require you to have this, but others do not. If you need an international driver's license, you can get this at any Triple A location with your United States driver's license.
Step4
The next decision for your rental car in Germany is determining what type of car you will need. A compact car in Europe is much smaller than one in the United States. Ask questions such as whether the car has a trunk or just hatchback, how many pieces of luggage will fit, whether the car has a GPS navigational system, and what type of gas the car will take.
Step5
Find out the policies of the rental car company. Do you need to have your driver's license and passport to pick up the car? Do you need to use the same credit card with you that the car was reserved with? Must drivers be over 25 and have held their license for at least a year?
Step6
Find out the working hours of the local rental car company where you will pick up your car. If you are arriving by train at 6 pm local time, but the rental car company closes at 5 pm, you will need to choose another option. Discuss this with the rental car company to find out the best alternative.
Step7
Confirm your reservation, and ask to be sent a copy by email. This way you can verify that everything is correct, including your special requests. Translate pertinent information into German, in case the local rental car company in Germany does not have English speaking people available.
Step8
Have contact information for the rental car company in Germany that you can call if there is a problem. Your train or plane may arrive late, and you may need to contact the local Avis or Hertz to let them know.
Step9
Make yourself a list of German phrases with the English translation of what you will need to know when picking up the rental car. For instance, if you requested a trunk, know how to say this in German, and know the possible responses in German.