CLEVELAND --For every new car purchased this year, roughly 3 used cars will also find new owners. Those used cars often look just as good as brand new models, and cost much less.

But underneath the paint and trim, a few of these cars may be hiding a secret: they've been involved in accidents and repaired. As a consumer, it's important to know the history of the car you are purchasing.

But without knowing what to look for, and without a detailed car history report, most buyers wouldn't know whether their used car is in pristine condition or has undergone major body work.

Last month, with the help of Ray Kemmer ofLiberty Ford and car history service CarFax, we took 3 used cars to SouthPark Mall.

Each car was a 4-door Ford Focus. They were either 2010 or 2011 models with between 40,000 and 60,000 miles. To the naked eye, each Ford looked as good as new.

But one of the cars wasn't like the others."It's been in an accident. It had to be towed from the scene. But it's been rebuilt and it looks just as good as the other two," explained Chris Basso, of CarFax.

We invited SouthPark Mall shoppers to take our challenge. Could they spot the rebuilt wreck?One by one they looked under the hood, started up the engine, open and shut doors, and crawled under the under-carriage.

They examined panels, and scoured over interiors. Each amateur inspector took a few minutes going over each vehicle before revealing their verdict.

"I think this one has been rebuilt," Phil Wetmore told us, pointing to a blue Focus.

"I'm thinking this one," said Patti Reece, also pointing to one of the blue models. Margie Lamers and Ed Veits also took our challenge and guessed one of the two blue models must be the rebuilt wreck.

Out of all the shoppers who took our challenge, not a single person correctly picked out the re-built wreck: the silver Ford Focus.

What was it they missed? Ray Kemmer ofLiberty Ford showed us.

"You want to look for what we call the fit and finish," he explained.

The silver Focus had been in a rear-end collision and underwent significant body work.He pointed out how the seam between repaired panels was slightly off. You can spot it by comparing all the seams of a car, which should be uniform.

"Often when someone is doing repair work to a vehicle, they will often replace a fender. They will remove and replace a fender and you can notice that by looking at the bolts and hardware that secures the pieces together," Kemmer said.

Look for scrapes on bolts where someone has used tooling to replace them. You may also find overspray on the under-carriage.

The entire back end of the silver Ford Focus was wrecked, repaired and repainted, but it took a car expert's trained eyes to point out the fix.

"The average consumer just doesn't know where to look or what to look for to spot signs of hidden damage. You need to consult the experts, get a CarFax vehicle history report and take it to a qualified mechanic before you buy it," said Chris Basso, of CarFax.

Basso showed us the report which detailed the accident, damage and repairs to the 2010 S-E.

"That's why it's so important for you to consult the experts and know what you are buying before you lay down your hard earned money," Basso added.

Here are some other signs that a used car is a rebuilt wreck:

  1. Paint that doesn't match indicates damage repair and poor matching.
  2. Paint overspray on chrome, trim or rubber seals around body openings can be a sign that an adjacent panel was repaired.
  3. Uneven tread wear reveals wheel misalignment, possibly because of frame damage.
  4. Mold or air freshener cover-up may be a sign of water damage from a leak or flood.
  5. Damaged/scraped nuts and metal on top surface of strut tower (which connects the front wheels to the frame) in engine compartment may mean the frame was realigned.

If you have to car shop at night, ask the dealer to pull the car into a lighted bay or garage so that you can inspect paint under brighter lights.