Just a few years ago, no one had ever heard of CarGurus — at least, it seemed that way. Now, the site is the number one car-shopping website in the United States, beating better-known names like Cars.com and Autotrader.com and launching a national TV campaign.

Just like comparing cheap car insurance rates, buying a used car seems complicated, but it shouldn’t be. That’s the basic philosophy behind CarGurus, which aims to build “the world’s most trusted and transparent automotive marketplace.” So does it live up to that promise?

What is CarGurus?

CarGurus has been around longer than you think. It was launched in 2006 by Langley Steinert, who’s co-founder of TripAdvisor.

The company looks at car shopping through a big-data lens, using data analytics and proprietary algorithms to answer the questions shoppers have: What’s a fair price? Is this the best deal around? Can I trust this dealer? Its best-known feature is the CarGurus Instant Market Value (IMV), which is the site’s own calculation of the fair retail price for a particular vehicle, based on comparable listings. It’s free for dealerships to post their cars, so CarGurus has a whopping 5 million vehicles listed, on average.

The model is working for CarGurus. Not only does the site see more than 30 million unique monthly visitors, it’s making big bucks from car dealers. But does it work for you, the consumer?

The Pros Of Using CarGurus

• It truly is unbiased. More than half of American car dealerships pay to post listings on CarGurus. The rest don’t. But CarGurus doesn’t discriminate by putting paying customers’ vehicles first. Instead, the best deals are listed at the top, followed by fair deals and then those that are priced over the Instant Market Value. (They do have sponsored listings, but these are clearly labeled.) Listings also get a boost if the dealer is rated highly by users.
• You can read dealer reviews. Never heard of a particular dealer? Reading CarGurus’ reviews by other buyers can tell you what to expect. “The sales crew was very courteous and they responded back to me in a timely professional manner” = good. “Stopped all communication once I told them I wanted to pay cash and not finance” = not good. You can also see how a dealer responds to negative reviews.
• CarGurus helps you negotiate. Maybe you feel a little queasy at the thought of haggling with the dealer over a car. Maybe you relish the thrill of hammering out a deal. Either way, a CarGurus listing can give you some valuable information when you’re buying a car. You’ll see how long it’s been listed on the site — if the car has been sitting there for months, you have some leverage. You’ll see how much the price has dropped, if at all, which may reveal how much lower the dealer is willing to go. And you’ll see how many other people have saved a car, too.
• You can get an Instant Market Value for your own car. Before you trade in or sell your vehicle, check its IMV on CarGurus.com. You might be surprised by the difference between that price and the Kelley Blue Book estimate, which is the traditional way to assess used-car values.
• You can sell your car with peace of mind. When private sellers list their car on CarGurus, they get up to $75,000 in protection for their secure, online transaction. CarGurus also can provide financing for the buyer.

The Cons Of Using CarGurus

• Communication with dealers can be spotty. The appeal of CarGurus is that it instantly connects buyers and dealers. When you see a car you like, you can enter your email and/or phone number to have the dealer contact you. But this system doesn’t always work to buyers’ satisfaction. Read enough reviews on CarGurus.com, and you’ll find lots of people who say they never heard back from a dealer or received a response too late.
• Car listings aren’t always accurate. Many CarGurus reviews tell the same story: A would-be buyer shows up at the dealer and then finds the advertised car has already been sold. Bummer. Our advice: If you really want a particular car, immediately follow up your online request with a phone call to the dealership to express interest and schedule a test drive. (Don’t be too enthusiastic, though, or you’ll lose your negotiating power.)
• There are few private auto sellers. Sometimes, the best deals on used cars come from private sellers. But most vehicles listed on CarGurus are on dealers’ lots. Private auto sales do have some downsides — like used car buying scams — but it’s nice to have the option.
• It costs money to sell your car on CarGurus. Listing your car is free — but you’ll have to pay $99 when you actually sell it.
• You have to jump through some hoops to sell your car. Some sellers complain about CarGurus’ requirement that you verify possession of the car. This means the site will pull your listing until you fulfill a very specific request: You have to send a photo of your car with one door open and a verification code either printed or written on a piece of paper in the windshield. CarGurus does this to deter scammers, but it’s still a pain.

Buying a car soon? Don’t forget to compare auto insurance rates on Compare.com so you can get the best deal. It’s free. It’s fast. And it’s easy!