This is the one-off Lamborghini Egoista, a concept supercar that Lamborghini built to celebrate its 50th anniversary in 2013.

It's called the Egoista - 'selfish' in Italian - because there's only one.

The idea was to keep it in a museum and not sell it, hence the name.

But Lamborghini received the proverbial offer that couldn't be refused and ended up selling it to a client.

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The one-off Lamborghini Egoista hides a relatively 'common' Lambo underneath it

Lamborghini often builds limited-edition vehicles like the Countach LPI 800-4, the Ultimae, and the Terzo Millennio, but the Lamborghini Egoista is special because it has become the most expensive Lambo ever made.

It was conceived as a gift from Lamborghini to Lamborghini, but the automaker ended up selling it to an elite client.

Interestingly, and most people would probably not be able to tell just by looking at it, this supercar uses the same chassis and engine as the Gallardo.

The 'selfish' single-seat setup meant that, to get in and out of the car, the driver needed to remove the steering wheel - like in a Formula One car.

Lambo also removed the windshield and roof, and replaced both with a fighter jet-style canopy.

And the fighter jet theme continues inside, with a head-up display and about a million buttons and switches, and also at the back, where with a striking dual exhaust system that looks like it was borrowed from an airplane.

They didn't do much to the engine, though.

Under the hood, you'll find the same 5.2-liter V10 as any other Gallardo, with a power output of 600hp.

The reported price tag is record-breaking

Private sales aren't unheard of, and automakers routinely sell extremely rare cars directly to customers.

Years ago, a Lamborghini Miura SV mysteriously failed to sell at auction because the auction house cut the auction short.

No reason was given, but years later, we discovered that it was because the automaker itself had stepped in and asked to buy it back for a VIP customer.

In this case, Lamborghini decided to sell this concept supercar because the offer it received was pretty generous.

We don't know the exact amount, but we know it's over $100 million.

This makes the Egoista the most expensive car ever made.

Technically, there's the case of the Invencible - not a typo, that's the car's actual name - which is another one-off Lamborghini concept that sold for an undisclosed sum, and no one even knew where it was until months ago.

But, precisely because we've no idea how much that went for, the Egoista, for now, takes the crown.

A closer look at the most expensive Lamborghini ever created, the $100 million Egoista