There's a reason the overwhelming majority of U.S. households own a vehicle. Having access to a car often makes life easier and more productive, especially when you compare the process of taking public transportation to that of getting into your automobile and taking off as you see fit.

On the other hand, buying a vehicle is something many people do each year even when they can't really afford it. And if you're new to the car-buying game, you might really end up in over your head. So before you make what could be your most substantial purchase to date, ask yourself these key questions.

Man handing car keys to another man.

IMAGE SOURCE: GETTY IMAGES.

1. Can I afford the monthly payment?

Most people are advised to keep their housing costs at or below 30% of their monthly take-home pay. But because owning a car is generally far less expensive than owning a home, the associated guidelines aren't as clear. As you explore your options, make sure you understand what sort of monthly payment each vehicle you look at will translate into, and only purchase a car whose payments you can keep up with. In fact, it pays to go into your vehicle search with a budget already in place so that you can see how much money you have available to spend.

2. Can I afford the maintenance?

Buying a car doesn't just mean making your monthly auto loan payment; it also means taking steps to keep that vehicle running. Before you buy a car, do some research to understand what its maintenance costs entail. Keep in mind that standard services like oil changes tend to cost far more for high-end vehicles than for regular ones, so even if you can swing the monthly payment, you might bust your budget on run-of-the-mill upkeep and repairs. Or, to put it another way, replacing a part on a $30,000 vehicle might cost $400, but that same part on a $50,000 vehicle might cost more than $1,000.

3. Am I paying for features I'll rarely use?

It's easy to get caught up in the excitement of heated seats and fancy navigation systems, but before you pay a premium for a vehicle offering such features, think about how often you'll really use them. If, for example, you live in an area that stays hot year round, seat warmers aren't something you're apt to take advantage of too often. Similarly, if the bulk of your driving tends to be local, you may not need that GPS most of the time.

The same logic applies to the size of the vehicle you choose to buy. Sure, it's nice to have the added room that comes with a spacious automobile, but if you live alone or don't have children, you might manage to get by with a more compact car instead. And doing so could save you a bundle. AAA estimates that it costs an average of $8,849 a year to own a car, but that figure drops to $6,777 per year for small sedans. Therefore, if you don't need the space, you stand to save more than $2,000 a year.

4. Should I buy my car used?

The average new car loses about 10% of its value the minute you drive it off the lot, and things only go downhill from there. In fact, new vehicles depreciate so quickly that it pays to consider buying a used one instead. So before you get your mind set on buying new, find a reputable dealer and see what certified, preowned vehicles it has to offer.

5. Should I own a car in the first place?

Just because you need a vehicle to get around town doesn't mean you must own it. If you don't expect to put heavy mileage on that car, a lease might be the better way to go. The benefit of leasing is that you get to unload your car the moment it might otherwise begin to show signs of major wear and require significant maintenance. On the other hand, there are plenty of drawbacks to getting a lease, so you'll need to weigh those against the upside.

Buying your first car is an exciting milestone. Answer these questions first, and you'll be more likely to make the right choice.

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