Things to be aware of when renting a car in Costa Rica:
1. Do not go with "Economy Rent a Car."
2. Read the fine print before reserving.
We found out that we needed to bring a letter from our credit card who covers accident insurance (damage we do to other cars/objects) to show the people at the rental agency. We would have paid a bunch more money had we not come prepared with this letter. Way to go Scott!
3. They will charge you for collision insurance. It was not quoted in the "grand total" price they give you when reserving. At economy, this insurance cost more than our car rental itself. At "Dollar Rent a Car" it cost half of our rental price. We did not find a way to get around this and believe there isn't one--- but let us know if you find a way!
5. Take photos of each aspect of the car before you ever turn the car on! Let them see you being aware of the scratches and dents, and jot down the name of the guy who helps you.
Also, consider getting a 4x4! The roads are rough and if you have a car that can handle the terrain, you're in for a terrific time!