How AutoCheck Works

AutoCheck uses a bunch of sources to come up with its scores, including:

"Automotive auctions in particular, where they're physically inspecting the vehicle," are good sources of specific information, Kator said.

Title Check: If the car's been salvaged, rebuilt or burned up in a fire, it'll show up on the title.

Odometer Check: If anyone's messed with the odometer at all, or if it's broken, it'll have been noted somewhere. Not even Ferris Bueller got away with odometer tampering on that Ferrari, remember. AutoCheck also alerts you if the miles seem suspiciously low, like a 1995 Toyota Camry with 10,000 miles (16,093 kilometers). Doubt it.

Problem Check: Aren't they all problems? Specifically, this section looks for frame damage, water damage (hello, Hurricane Katrina!) and if the car has earned official lemon status.

Use and Event Check: This is where you find out if the car's been ridden hard and put away wet, as they say. Rental cars, police cars, taxis, and government-use vehicles may have seen some hard miles, but they've also been treated to regular maintenance, Kator pointed out. Cars that have been in accidents or stolen may not have been so pampered, but that'll show up here, too.

Of course, none of these checks take into account maintenance records or condition, like rips in the seat or stains on the carpet. Those are the kinds of things you're just going to have to see for yourself.

AutoCheck allows you to know as little or as much as you like about the history of a vehicle. Some of us are already so overwhelmed by the car-shopping process that we glance at the score in the blue box on the first page of the vehicle history report and call it good. Or bad, depending on the score.

A quick glance at the vehicle comparison is a good idea, too -- that is, if you can bear doing just a tad bit more. It'll give you a range of typical scores for vehicles like the one you're looking at, which will tell you if this car's score is good or bad. Say the vehicle that makes your heart go pitter-pat gets a lousy-ish score of 40. Under that pathetic number, it says "Similar Vehicles Score" and gives a range. Turns out, cars like the one you so strangely love usually rate even worse! Hurrah! The car you want to buy is the best of a sorry bunch! Congratulations.

On the other hand, if the vehicle scores an acceptable 75, but its automotive peers range from 85 to 95, your impending purchase may be wearing the equivalent of an automotive albatross. Sorry, but you're going to have to delve a bit deeper to find out what mechanical or structural curse is hampering your potential car. Or just move on to the next candidate.

Some of us are detail-oriented nerds who will stop at nothing, not even page after page of scores, to know everything possible about the vehicle we're considering. These people will see the summaries at the bottom of the first page of the report as insulting. Summaries! Who do they think you are? A clueless Kardashian? Drilling down into AutoCheck's information and scores, including the full history (or at least as full as AutoCheck can manage), will give you the most complete picture of where your dream used car stands. It'll even give you case numbers for accidents that were reported to the police.

With all this information, though, there's still an important piece missing: price. AutoCheck just doesn't get into that. It does, however, have partners like the NADA guide, Kelly Blue Book, Edmunds.com and Ebay Motors where there are more prices than you can shake a dipstick at.

So let's say that you've shelled out literally dozens of dollars for this report and were provided a rating. You're about to take AutoCheck's word for the worthiness of this steel and fiberglass beauty and plunk down a much bigger chunk of cash for the car. But before you do, you might rightly wonder, does AutoCheck have your back?

It does. Mostly. AutoCheck's buyback protection will give you 110-percent of the NADA guide retail price of your car if, after you buy it, you find out it did have a sizzling hot branded title or had seen time as a Los Angeles police cruiser. They'll even reimburse you for up to $500 in aftermarket parts, so that bumpin' stereo you installed in your "vintage" 1999 Dodge Neon isn't wasted.

Since you asked, here are the hoops you're required to jump through if you want AutoCheck to buy back your used car:

If your car wasn't the LAPD cruiser but rather the stolen car the cop was chasing, the buyback policy does not apply to you.

Also keep in mind that a car's AutoCheck score will change over time as new information comes into the database. Things like accident reports and emissions scores are almost always going to change, but once a branded title, always a branded title. If you pay a bit more, you can run the VIN of the same car over and over and over -- if you're really that worried about it. But honestly, if you're that nervous, maybe your time would be better spent looking at a different car.

Verifying the shifty things people do to their cars is a tricky business, and AutoCheck knows it. Not every accident is reported, for a variety of reasons. Why report a little scraped paint and a dinged fender if you can tap out the bumps and spot-repair the paint? Why report a landscaping truck backing nearly over your hood if your brother can replace the front end at his shop after hours? He's got paint that will mostly match if you look at it under one of those sodium-yellow streetlamps. No biggie.

Consumer Reports did a check on AutoCheck and CarFax and found they both did a reasonably good job of reporting exactly what they promised -- but there were a few issues. They compared clean reports with pictures of the same cars on auction Web sites and found cars crumpled beyond recognition in some cases. "Wrecks can maintain clean titles if the vehicle doesn't have collision insurance, is self-insured as with many rental and fleet vehicles, or has damage falling below the 'total loss' threshold, which can vary by state," according to the report [source: Consumer Reports].

Despite that, Consumer Reports did recommend using automotive history reports, as well as a few other lesser-known sources, for checking out a car's sordid past:

There's also no way for you, dear consumer, to verify those happy green checkmarks on an AutoCheck report. However, you can -- and absolutely everyone recommends this, including Lynn Kator at AutoCheck -- take any used car you're seriously considering buying for an inspection by a professional.