As a crypto hodler you're well aware of it: holding digital tokens with the hope of it going up.
There's more to hodling than simple crypto
I bought some LEGO stuff today, with the idea of reselling it to collectors in 2-5 years short-mid term.
Goes End Of Live this year, allegedly
However, and this is important, you can not just buy anything. You have to search for products which go EOL (End Of Live) soon - supply dries out with a growing demand = increase of value. If you're in to crypto or other collectibles you know how it works.
LEGO does not officially announce when they take a product off production, so you need to google for inofficial resources. In general you want to search for licensed products.
The Christmas Advent Calendars go usually EOL after one season, so the supply is immediately shrinking. And I love Harry Potter :D
A Tip in need
If you have the opportunity, go buy the stuff directly in the LEGO shop. They offer great rebates and bonus for buying in the shop.
Plus,
you'll get stuff for free, which can also jump up in value over time. In total I got $15 worth of LEGO for free for shopping. Not bad!
The only downside is, you may have guessed it already: Storage. You can not build this stuff (=value kill for collectors), so you need to keep it dust and humidity free somewhere secure...