Hi everyone,
We are two German guys doing a one year volunteer service in the Pennsylvania.
At the end of our year in the here in August 2013 we´re looking forward to driving a loop through the country ending up back in Philadelphia .
We both own a German and an international drivers license since two years.
At the particular time of our journey we will be 20 and 19 years old.

Our plan is to buy a car to do road trip and sell it afterwards.

We already thought about renting a car but since our age, that would be too expensive and nearly impossible.

We think buying a car is no big problem.
We worry about the registration and even more about the insurance.

Is it possible for foreigners under 21 to resistrate a car and do a road trip?

We read a lot in forums and the internet but could not find a fitting answer.

Do have any experience or recommandations for us?

We would be very glad about answers and advices.