European classics make up many of the world's most expensive and desirable models. There's a model for every collector, from quirky cars like the original Mini Cooper to insanely expensive billionaire's toys like the Ferrari 250 GTO. To keep their cars in top condition, many owners opt to send their pride and joy to a specialist for a meticulous restoration.

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Restoring a car not only preserves it for the future, but it adds value and makes for a smart investment for collectors looking to maximize returns on their cars. However, not every stunning classic gets the same level of love and appreciation as the most famous models do. There's plenty of cars out there that are genuinely brilliant models but are only appreciated by a niche crowd or even not appreciated at all. Not only do underrated classics make for great investments, but they're also sure to break necks at car shows too, especially if they've been perfectly restored.

10 BMW 530 Motorsport Limited Edition

BMW 530 Motorsport Edition
Via BMW South Africa

There's so much praise heaped on BMW's M range of cars that it's easy to forget that the brand has made heaps of other stunning models that don't get as much recognition. One such model is the 530 'MLE', which was sold as a limited run of 530 units by BMW South Africa.

BMW 530 Motorsport Edition
Via BMW South Africa

Only one of those cars survives today, and it was recently restored and displayed by BMW themselves. It's not for sale, but buyers on the hunt for a bargain Bimmer to restore should dig around and see what other special editions are out there before opting straight for an old M car.

9 Lamborghini Diablo

Lamborghini Diablo
Via Classic Driver

The Diablo has only recently reached the age where it could be considered classic, but it's already become a seriously collectible model. Prices are steadily rising as decent-condition examples become more and more difficult to find.

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Lamborghini Diablo
Via Classic Driver

The car represents the height of an era where Lambo didn't care about practicality or mass-market appeal, and instead just wanted to create the craziest car possible. They don't carry the same price tag as other Lamborghini classics like the Countach or Miura yet, so anyone looking for a solid classic car investment would do well to consider a Diablo.

8 Rolls-Royce Phantom V

Rolls-Royce Phantom V
Via Lunaz Design

They're sometimes written off as old English gentleman's cars, but classic Rolls-Royces have an undeniably imposing presence that just isn't found with any other classic model. Cars like the Phantom V aren't actually that expensive to buy either, at least not by vintage car standards.

Rolls Royce Phantom V
Via Lunaz Design

They're not to everyone's taste, but those in the market for something a bit different could easily pick up an un-restored example, and then they'd have the freedom to upgrade it as they see fit. The example pictured above has been converted to electric power, but it's an equally good idea to fit a loud V12 under the hood. Either way, it makes for a pretty unique classic car.

7 Alfa Romeo Giulia Sprint GTA

Alfa Romeo Giulia Sprint GTA
Via Girardo & Co

The modern-day Giulia is a great car that's a serious competitor to the likes of the BMW 3 Series and the Mercedes C Class. But, many car fans aren't aware of how long the nameplate has been around.

Alfa Romeo Giulia Sprint GTA
Via Girardo & Co

The original run of the Giulia produced some of the best-looking Italian classics of the era, although they're currently very underrated in the collector's market. Some owners like to restomod their cars with vintage racing gear, but even just left stock, the car is sure to turn heads at any concours or car show.

6 Volvo 142S

Volvo 142S
Via Petrolicious

Many classic car lovers don't have tens of thousands to spend on purchasing their new pride and joy, but that doesn't matter. It's still possible to get a great Euro classic without spending too much money. The Volvo 142S is a prime example, as cars in good condition can be found for under $15,000.

Volvo 142S
Via Petrolicious

The bonus here is that these old Swedish classics are basically bulletproof, with the kind of reliability most modern cars could only dream of. That means it'll be fairly easy to keep lots of the 142's original parts, which both saves money and adds authenticity to the car. As reported by Petrolicious, it's surprisingly easy to restomod the car into a Scandinavian classic muscle project, too.

5 Maserati 3500 GT

Maserati 3500 GT
Via Dyler

Classic Maseratis are a niche market sector, which is why many classic car hunters might overlook them. Unfortunately, they're also generally a very expensive one, way out of the price range of most enthusiasts. But, for those who do have the cash to spend, buying a classic Maserati like a 3500 GT gets them entry into a very exclusive club.

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Maserati 3500 GT
Via Dyler

It's the kind of classic car that might seem unremarkable to a casual passerby, but to those in the know, it's a very respectable model to restore. They're bought mainly by fans of the brand or discerning collectors who want a car that looks great and drives well too.

4 Aston Martin DB2/4

Aston Martin DB2/4
Via Dylan Miles

Everyone knows about the DB5, what with its famous appearance next to a certain Mr 007. But, fewer fans appreciate the DB models that came before it, which is a shame as they're seriously good-looking cars.

Aston Martin DB2/4
Via Dylan Miles

Aston Martin actually has a special division of their team dedicated to the restoration of their classic models, but there's plenty of independent restorers around too. As with most Astons, buying and restoring a DB2/4 will be a seriously expensive business. But, when it's finished the car sports a certain kind of elegance that very few models can match.

3 Land Rover Series III

Land Rover Series III
Via Pinterest

A true British icon, the old Land Rover is well-loved for a reason. Since its launch in the late '40s, the Land Rover has seen all sorts of spin-offs and special editions, but it's hard to beat an old-school restored example.

Land Rover Series III
Via: Motorious

It won't be powerful, and it certainly won't be fast, but it's still just as able to traverse rough terrain as it was when it first rolled out the factory. Most restored Rovers won't be going anywhere near dirt though, instead being kept as mint examples of one of the greatest off-roaders of all time.

2 Lancia Aurelia B20GT 'Outlaw'

Lancia Aurelia B20GT Outlaw
Via NetCarShow

The Aurelia B20GT sits squarely in the 'forgotten' section of the Italian brand's lineup, but one restomodding company decided to change that and built the Outlaw. It's a hand-built restoration that takes the car's original 2.5L V6 but boosts power to 180 hp.

Lancia Aurelia B20GT Outlaw
Via: Pinterest

British restoration specialists Thornley Kelham were the brains behind the idea, and plan to build just nine of these specially restored Lancias. Several have already been sold, but the company's website implies there are still some build slots available. The price for one of these classic Italian street racers? It's strictly on request, of course.

1 Mercedes-Benz 600 Pullman

Mercedes-Benz 600 Pullman
Via Car and Classic

Modern limousines have a slightly tacky reputation, conjuring up the image of stretched Hummers and Town Cars shuffling drunk hen parties to nightclubs. But, a few decades ago, a limousine was a seriously prestigious car to have. It signified power, wealth, and status.

Mercedes-Benz 600 Pullman
Via Car and Classic

One of the most prestigious of all was the Pullman, an ultra-luxurious stretched version of the Mercedes 600. It was popular with government officials and celebrities all over the world. Everyone from Elvis Presley to Kim Jong-Un has owned a 600, so any examples for sale today have likely had at least one famous owner before.

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