Knowing what to do, and what not to do, when buying a car can mean the difference of hundreds or even thousands of dollars over the term of your loan and the life of your vehicle. Here are five tips for purchasing your first car seamlessly.

Get approved for financing

When you get approved for financing before you enter negotiations with a dealer, you force the dealer to match or beat the rate your bank or credit union has already offered. This step essentially gives you a bargaining chip to enter negotiations.

"If you have no backup plan, you're stuck with whatever the dealer is willing to do," said Brian Moody, site editor at Autotrader.

Don't string out payments

Signing on to an extended loan can add hundreds or even thousands of dollars to the price of a vehicle. People often seek longer loans because they're buying a car they can't actually afford.

"Practically anything seems affordable if you break it up over enough payments," said Joe Wiesenfelder, executive editor of Cars.com. "This is what leads shoppers to lose sight of the car's purchase price."

Shop for the best interest rate

The interest rate on your loan is just as important as the price of the car. A deal on a car's price isn't good if the exorbitant interest rate on your loan is going to jack up the overall cost over time. Remember that credit unions often offer lower interest rates than big banks.

Know your credit score

There is a direct correlation between your credit score and the loan you'll be able to secure. Your FICO credit score, which ranges between 300 and 850, is an approximate representation of the risk you pose to lenders.

Work on raising your credit score before purchasing

Use the time that you're car shopping to boost your credit score.

One of the fastest ways to quickly boost a score is to pay down credit card debt, because credit-card utilization carries a lot of weight with credit reporting agencies.

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