Gold sounds like a good way to invest your money, but it won't bring you back as much as retired LEGO sets will!
According to the report from HSE University that was published in the Research in International Business and Finance journal, older LEGO sets can really pay off in the resale market.
Looking at over 2,000 LEGO sets from 1987 - 2015, HSE University found that the bigger and smaller sets were the best ones to buy and hold on to. The smaller ones can have rare and collectible pieces, while the bigger ones are usually only made in a limited quality. Both of these factors can make them solid investments and get you a good return, sometimes even higher than gold, stocks or bonds! Some of the sets that are highly sought after include Millennium Falcon, Taj Mahal, Death Star II and Cafe on the Corner.
Of course this takes hard work and patience but there is money to be made!