People looking to make money could do worse than investing in LEGO. A 2018 study found that buying new LEGO sets to sell later yielded greater returns than stocks, bonds, or gold. Some LEGO products are more likely to multiply in value than others (e.g. anything with the name Star Wars on the box), but if LEGO collectors want to know if their old toys are worth cash, they should start by looking for these sets.

1. Millennium Falcon

LEGO is known for its elaborate Star Wars sets, and its Millennium Falcon model is the most sought-after of them all. The 7541-piece Ultimate Collectors Series edition, an update of the 5197-piece Millennium Falcon, hit the market for $800 in 2017, making it the priciest set the company had sold at the time. The toy was only around for a limited window, and now it sells on websites like eBay for more than $2000.

2. Hogwarts Castle

LEGO delighted Harry Potter fans when it released a detailed replicate of Hogwarts Castle in 2018. The set, which has over 6000 pieces, is a masterpiece of interlocking brick architecture. All of the building features that fans remember from the films—including the chambers, towers, classrooms, and even the Whomping Willow—are recreated in the toy model. Lego sells it for $400.

3. Taj Mahal

The 5922-piece Taj Mahal broke the record for most LEGO pieces per set when it debuted in 2008. That record has since been toppled by the 2017 Millennium Falcon, but the Taj Mahal is still legendary among LEGO collectors. It originally sold from LEGO for $300, and today buyers are willing to spend thousands on the classic set (Wal-Mart has two sets left, which are going for nearly $1500). The Taj Mahal model is so popular that LEGO relaunched the set in 2017. It's still available at the LEGO shop for $370.

4. Eiffel Tower

This 1:300-scale Eiffel Tower set from LEGO stands more than 4 feet high when assembled, making it one of the tallest LEGO sets ever made. The toy maker released the set in 2007 for $200, and while other Eiffel Tower LEGO models have been manufactured since then, none can compare to this stately structure. The set is currently available for $2757 on Amazon.

5. Death Star

The Death Star is another valuable Star Wars-themed product in LEGO’s collection. This set, featuring 4000 pieces, is available for $500 from the LEGO shop. When assembled, the 16-inch-high (and wide) model is good for more than giving your Luke Skywalker minifigure something to fly around; the interior chambers are exposed, so you can recreate several scenes from the film.

6. Cafe Corner

Dutch Treat, Flickr // CC BY 2.0

In 2007, LEGO released the Street collection, which featured eight separate sets of buildings you would find on a city block, such as a pet shop, firehouse, and movie theater. The Cafe Corner set in this collection, featuring a little over 2000 pieces, sold for around $100 upon its release. Today it’s available on Amazon for close to $2000.

7. Disney Castle

The castle at the center of Walt Disney World in Orlando, Florida, is available as a LEGO set. The LEGO shop sells the 29-inch-tall Disney Castle for $350. With the 4000 pieces that come in each box, builders can construct a five-level palace that’s fit for a princess—or at least fit for the Mickey, Minnie, Donald, Daisy, and Tinkerbell minifigures included in the set.

8. Grand Carousel

With 3263 pieces, nine minifigures, and a motorized, rotating platform, the Grand Carousel is one of the more impressive sets ever released by the LEGO company. Even though it’s not attached to a particular property, it’s prized by collectors, fetching more than $2000 on online marketplaces. The set debuted at $250 in 2009 and was discontinued roughly a year later, and its limited availability drove up its value.

Mental Floss has affiliate relationships with certain retailers and may receive a small percentage of any sale. But we choose all products independently and only get commission on items you buy and don't return, so we're only happy if you're happy. Thanks for helping us pay the bills!