When an auto loan deal goes wrong, it's often because of problems that occur when the contract is prepared in the finance and insurance office (the "F&I" room). It's here that a car buyer can see much of the potential savings regarding his or her auto loan go up in smoke.To better inform car buyers, we contacted a finance expert and a former F&I officer to find out what typically goes wrong and how these problems can be avoided.

Brian Reed, director of Internet lending for Capital One Auto Finance (formerly PeopleFirst), said, "Most consumers have front and center the information about the cars that they want to buy. But then they go into the finance office and all the savings could go out the door."

Another auto loan expert contributing to this article worked as an F&I officer in dealerships for 15 years. He asked that his name be withheld because, as an auto wholesaler, he didn't want to alienate dealers. However, he said that most consumers "aren't aware of the importance of the F&I experience. They view it as paperwork that should be completed as quickly as possible so they can drive away in their new car."

First and foremost, the deal agreed upon by the salesman needs to be put in writing in the contract, our unnamed source advised. This often involves determining monthly auto loan payments based on an interest rate. Sometimes, the interest rate a customer qualifies for is inflated so the dealership can make extra profit.

This and other F&I headaches can easily be avoided by obtaining independent auto financing before going to the dealership, Reed advised. This means the consumer can proceed as a "cash buyer" and negotiate only the price of the car. Car salesmen prefer customers to be "monthly payment" buyers because, in this way, it is easier to obscure the total cost of the vehicle.