Grumpy Old Geeks Topics Lego set resale values Topic Lego set resale values 2 mentions in 1 episode The hosts discuss a reported study of aftermarket returns for discontinued Lego sets. Mentions 360: Slackers Jul 13, 2019 1:12:53 There was a 2018 study that looked at 2,322 kits dating back to 1987. 1:13:29 Bigger sets like Harry Potter or Star Wars themes yield an average return of 11% annually.