Cars that have a special place in automotive history don't come up for auction very often. They stay in garages of car collectors. With the market prices of some classic cars being incredibly high – it can get up to millions for a Ferrari – vintage vehicles become a good investment. The value of classic automobiles has risen over 500% since 2005. If the car was expensive when it was released, then it's very likely that it would have a higher value decades after.

Car collectors look for well-made vehicles and quality workmanship. If the vehicle is made with quality materials, it would have a high value that would probably increase with time; provided it's maintained and cared properly. Some cars keep their value better because some brands have an enduring popularity. Popularity also depends on the car's overall appeal. Here are 15 most expensive Mustangs and Camaros ever sold at auction.

15 2008 Shelby GT500KR - $550,000

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Ron Pratte, who owns many Shelby Mustangs, paid $550,000 for the 2008 Shelby GT500KR. It features a beautiful black-on-black paint scheme and looks incredible with a glass roof. Carol Shelby was on hand to send the car off, that's why the price is so high. All the proceeds went to the Juvenile Diabetes Research Foundation.

RELATED: 15 Things Nobody Knows About Ford Mustangs

14 2007 Shelby GT500 - $600,000

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The winner of the auction paid $600,000 for the 2007 Shelby GT500 at the 35th Anniversary Barrett-Jackson World's Greatest Collector Car Event. This car is an interpretation of the King of the Road Mustang. Thanks to the 5.4L V8 engine with Ford GT-derived components, this was once the fastest Mustang ever produced.

13 1968 Camaro Z/28 Penske Trans Am Racer - $990,000

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The Camaro Z/28 Penske Trans Am Racer was driven by Mark Donohue for a 2nd place finish at the Daytona 24 Hours in 1968. In 1967, Roger Penske teamed up with Donohue and came up with this unique model with a lightweight body. In 2016, it was sold for $990,000 at RM Sotheby’s Amelia Island.

12 1969 Mustang Boss 429 - $605,000

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Getting $605,000 for the 1969 Mustang Boss 429 is an achievement. Even though this car is rare, it never commanded so much money. However, this model is one of the first Mustangs made by hand. It features an 820-S NASCAR engine with heavy-duty half-inch bolt rods. Ford wanted this car to be accepted by NASCAR.

11 2007 Shelby GT - $660,000

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When it comes to charity, Ford has been known to auction off special Mustangs for charitable causes. One of these cars is the very first 2007 Shelby GT. This model has unique authentication plate and performance upgrades. Proceeds from the $660,000 sale price were donated to Carroll Shelby's Children's Foundation.

10 1969 Camaro ZL1 - $848,000

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GM policy basically forbade installing big-block engines in the Camaro, but dealers and racers found a way around the rules by using the Central Office Production Order (COPO) program. The most desirable of these big-block Camaros is the ZL1, which featured an all-aluminum, hand-built 427 with roots in Can-Am racing.

9 1969 Shelby GT500 Convertible - $742,500

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In 1969, Carroll Shelby and Ford parted ways. In 2008, The 1969 Shelby GT500 Convertible sold for an amazing $742,500. The original owner was Mr. Carroll Shelby himself who used the car for several years. It was featured in many ads and shots. It was also a subject of a lengthy restoration process.

RELATED: Get Seduced By These 15 Ford Shelby GT350 Photos

8 1965 Shelby GT 350 R - $990,000

motor1.com

Of all the first-generation Shelby Mustangs ever built, only 34 were ever christened GT350 R models. When this car crossed the block at RM Sotheby’s 2012 Monterey auction for $990,000, it did so with a verifiable racing history and was presented in exceptional racing condition, right down to the Plexiglass windows.

7 1969 Camaro ZL1 - $715,000

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This 1969 Camaro ZL1 is the 4th ever built, and it's in a perfect condition. The Camaro ZL1 was among other cars delivered to Illinois dealer Gibb Chevrolet. The $715,000 price tag can seem a bit ambitious, but the 1969 Camaro ZL1s are extremely rare, and this one was sought after.

6 1967 Shelby GT500 Eleanor - $1 Million

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This 1967 Shelby GT500 Eleanor was used during filming of Gone in 60 Seconds and sold at auction for $1 million. The car was driven by actor Nicholas Cage in the movie's closing stages. Eleven of these Mustangs were created for the movie, but only 3 were real cars, and 2 were destroyed.

5 2020 Shelby GT500 - $1.1 Million

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Barrett-Jackson CEO Craig Jackson got the first 2020 Ford Mustang Shelby GT500 to come off the production line. The proceeds from the $1.1 million sale price were donated to the Juvenile Diabetes Research Foundation. The green color isn't one of the factory hues, it's a custom apple green developed by BASF.

RELATED: 15 Photos That Show How Much The Shelby GT500 Has Changed In 50 Years

4 2014 Camaro COPO - $700,000

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To many people, spending $700,000 on a Camaro is the craziest thing in the world, but this 2014 Camaro COPO sold at the Barrett Jackson auto auction is as far as you can get from a normal Chevy. This is one of 69 units that were made for the 2014 model year.

3 1967 Shelby GT500 Super Snake - $1.3 Million

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This rare 1967 Shelby GT500 Super Snake sold for the price of $1.3 million, making it the most expensive Mustang to ever sell at auction at the time. It’s the only one of its kind, built with a 427 cubic-inch race engine similar to the mill in the original GT40."

2 1968 Mustang GT Bullitt Hero Car - $3.4 Million

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The most iconic of all Mustangs is this 1968 Mustang GT Bullitt Hero Car that starred in Steve McQueen’s seminal "Bullitt". Even though 2 different models were used for filming, this one was sold at the world's largest auction in Kissimmee, Florida. The current owner, Sean Kiernan, revealed the car at the Detroit Motor Show.

1 2014 Camaro Z/28 - $650,000

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Rick Hendrick added the 2014 Camaro Z/28 to his collectibles, thanks to his $650,000 winning bid during the Barrett-Jackson Scottsdale auction. The car comes with a 7.0L LS7 V8 delivering 505 hp and 481 lb. ft. of torque, equipped with a 6-speed manual transmission. Mind you, the MSRP on the king of Camaros is $75,000.

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