In most cases, your car is a depreciating asset that will gradually shed its value over time. Or, in the case of some full-size luxury cars like a BMW 7 Series, expect to see well over half the car's value tumble off a cliff in the first five years of ownership. This is not a problem that affects the Ford GT - in fact, used versions of the all-American supercar are now fetching insane prices that are, in some cases, up to three times the original $450,000 price, according to a report from CNN.

That's an exorbitant amount of money to spend on any car, but there are several factors at play that have contributed to the GT's ballooning value.

Back when the initial batch of second-generation GTs was sold in 2017, buyers had to sign a waiver stating that they couldn't sell their cars for at least two years. In case you haven't noticed, it's 2020 and this agreement has now lapsed. Ford GT owners are quickly taking advantage, and just a few days ago, one of the supercars was auctioned by RM Sotheby's for an unreal $923,500.

In case you're wondering why buyers wouldn't simply opt for a new GT, well, extremely limited production numbers mean that they're particularly hard to get hold of, not to mention Ford's exclusive allocation process for 2017/2018 models.

The RM Sotheby example isn't the only GT that costs about the same as a New York City apartment. Barrett-Jackson also got in on the action and sold two cars for $1.2 million and $1.5 million, although this does include the auction company's 10 percent buyer's premium. Still, it's an astonishing amount of money for a car, even one with 647 horsepower, looks to kill, and the driving dynamics of a racing machine.

With Ford GT sales increasing by 82 percent last year (229 units in total), it seems that Ford made the right decision to increase its overall production of the supercar from 1,000 units initially to 1,350 until 2022, although only 600 GTs have so far been delivered.

The question is, will used GTs continue to rise in value or is there an end to the madness? It seems that the answer is the latter, as bidding for a Ford GT at a Mecum Kissimmee auction in Florida went all the way up to $1 million, but the car's owner wasn't quite happy with that and the car remains up for sale. "I think the prices on the secondary price market will not go up over the next two years," said Karl Brauer, executive editor of Kelley Brook and the owner of a GT himself. "It'll probably go down. How much it goes down is harder to predict."

Another GT owner is Craig Jackson, CEO of Barrett-Jackson, who expressed surprise that owners are letting go of the iconic supercar despite the colossal return on investment. "I'm a little amazed that so many guys that made that hard cut are selling them with no miles on them."