Whether it's your first time or you're a seasoned pro, you should never buy a car on impulse. The buying process takes time, research, careful thought and even some strategy.

Truth be told, it can be overwhelming. In addition to finding the best car for the right price, you have to navigate through confusing payment options and deal with salespeople. One mistake -- no matter how small -- can cost you hundreds, if not thousands, of dollars.

Under such pressure, it's easy to understand why so many car shoppers get in over their heads. However, it doesn't have to be that way. By learning from past mistakes, you can find the right car and get a good deal too. Take a look at eight of the most common car buying mistakes and how to avoid them.

1. Confusing Wants with Needs

Convertible two-seaters are really cool. But if you're lugging a load of hockey equipment every day, chances are you'd do better with a Honda Fit than a Mazda Miata. Unfortunately, car shoppers often make the mistake of confusing their wants with their needs. After all, who wouldn't want a car that's faster, sexier or more luxurious? However, such choices aren't always practical...or even affordable.

Avoid making the same mistake by putting together a list of regular activities that would require using your car. When car shopping, reference the list to make sure that the car you're considering will serve those functions well.

2. Test-Driving the Wrong Trim

You know those weird letter-number combinations that follow your car's badge -- LS, GLS, LX, LP560-4? In most cases, they denote significant performance, interior and even exterior differences between trims of the same model. The Dodge Challenger SRT8, for example, performs like a true American muscle car. The Challenger SE? Not so much.

Be wary of dealers who give you the highest trim level of a car to test drive and then proceed to sell you a trim that better fits your budget. Car shoppers who fall for this trick usually end up sorely disappointed with the car's performance and features. To avoid making this mistake, test drive the exact trim you plan to buy before signing any papers.

3. Sacrificing Reliability for Appeal

Don't let a car's curb appeal or features sway you. Buying a pretty car with funky features and a poor history of reliability can prove to be a major drain on your wallet. Just ask anyone who has purchased a Volkswagen Jetta. Shoppers love the Jetta for its small size, cute design and sprightly performance. However, the vehicle has a so-so record of dependability -- receiving a J.D. Power rating of only 2.5 out of five power circles for predicted reliability.

Before you allow a car's emotional statement to overpower your ability to think rationally, research its reliability. J.D. Power and Associates is a good source for determining whether your car is doomed to be a lemon. If you're buying a used car, hire a mechanic to conduct a pre-purchase inspection.