But Forbes reports that the performer's estate has made millions more since his death - both from auctions of his collections and memorabilia and from music that's still being played and marketed today.
Michael Jackson topped Forbes' list of the highest-paid dead celebrities of 2018 after raking in around $400 million that year alone.
But before he died, the singer was millions of dollars in debt. According to William R. Ackerman, a forensic accountant, Jackson was spending thousands of dollars more than he was making.
Ackerman, who testified in a 2013 case involving the singer, reportedly said that Jackson was making $30 million-a-year payments toward his debt at the time of his death. But Ackerman said he was simultaneously spending lavishly on things like jewelry.
It wasn't a secret that the king of pop had a bizarre fleet of collectibles, but it wasn't until he died and things were put up for auction that the public got to see the full roster.
He owned the gloves Johnny Depp's character wore in "Edward Scissorhands" ...
... several replicas of his own face in different expressions ...
... a robotic replica of his head as seen in the "Moonwalker" film starring Jackson ...
... and life-sized figures of fictional crime-fighters like Batman ...
... Superman ...
... and Spider-Man.
He also had figures of sci-fi characters like E.T. ...
... Yoda ...
... and villains like Darth Vader.
His Neverland Ranch featured a fully-functioning arcade with loads of games available for playing.
The arcade was located in the pool house on the property, according to the Associated Press.
According to NBC, Jackson paid $1.5 million for the Academy Award statue that was awarded to 1939's Best Picture winner, "Gone With the Wind."
He reportedly displayed the statue on a rotating stand next to the fireplace in the home's main living room.
Forbes reported that Jackson purchased the oil on canvas painting seen below for $46,000. The painting, called Cleopatra's Last Moments, was reportedly signed by the artist, D. Pauvert, and dated 1892.
The Neverland Ranch was an enormous expense for Jackson. Entertainment Weekly reported that the singer paid $19.5 million for it in 1988.
Jackson also made additions to the property and house, like the Disney Parks-themed train station ...
... a working train that passed through the station ...
... and bronze statues of children that littered the property and could be seen from the train as it went around the grounds.
Some of the statues were available for purchase at the 2009 auction.
Entertainment Weekly reported that, at one point, it cost Jackson $10 million to keep up the ranch and all of its amenities, including the train, theme park, zoo, and theatre.
Neverland Ranch was filled with hints of glitz on the inside, too, like the gold-colored, goose-like spout on the star's bathtub.
While the amount he spent on building and furnishing Neverland Ranch hasn't been confirmed ...
... certain items like the front gate pictured here had an estimated price tag of up to $30,000, according to Forbes.
Jackson wasn't living at the ranch at the time of his death, though. He was reportedly paying $100,000 a month to rent this Bel-Air mansion, according to Forbes.
He also collected cars, like this personalized Rolls Royce limousine.
The limousine was customized by Jackson and featured leather seats and an embellished ceiling.
Jackson's spending didn't stop at cars. In the early '80s, he famously purchased a pet chimpanzee named Bubbles.
According to Newsweek, Jackson's "extreme debt" dates back to 1994 when he owed $30 million.
Billboard reported that it was the 1993 legal battle — when Jackson was accused of molesting a 13-year-old boy — that benchmarked the turning point in Jackson's career as well as his mental, physical, and financial health.
Jackson reportedly paid the family $25 million in 1994.
While he was spending on going to trial in the '90s, Jackson was still making money. He was collecting roughly $75 million a year during that time from owning the rights to his music library as well as that of the Beatles — which he bought for $47.5 million in 1985 — according to The Daily News. Still, he reportedly spent more than he made.
The 2009 auction was actually planned before the singer died in June. It was set to feature items belonging to Jackson himself as well as collectors around the world.
At the 2009 auction, the iconic, white spandex, Swarovski-encrusted glove that became synonymous with the King of Pop sold for $350,000.
Julien's auction house estimated the worn-in, sweat-stained glove would sell for up to $200,000.
Forbes reported that just before the auction was set to take place, Jackson had made between $200 million and $300 million from his planned London concert tour.
The day before the first public exhibit of belongings on offer, Jackson filed a lawsuit against Julien's to prevent the auction from happening. The suit ultimately resulted in Jackson paying a reported $2 million worth of expenses — plus an undisclosed additional amount — Julien's had already taken on in planning the auction.
Since his death, Jackson's belongings — like this "Smooth Criminal" hat and family notebook ...
... and memorabilia have been auctioned off around the world for thousands of dollars.
But, that doesn't necessarily mean the singer paid high prices for those things when he first acquired them.
Even so, the things he did spend on — like the acres and acres of trimmed grounds at the Neverland Ranch — set him back quite a lot.