My eldest has loads of Jellycat toys. Says the most maddening thing is that she was collecting them long before they became a 'thing'! I also bought them some Jellycats when they were little so pieces 20+ now.
God I have a tonne of stuff round my house that must have cost a fortune. I started collecting Denby dinnerware and I have every single thing that was issued in my range in the last 35 years. Recently replaced a few plates and added more, using Tesco Clubcard which I learned about on MN.
I have two Wedgwood dinner services, one with all the bells and whistles, serving dishes, bread plates, teacup and saucers, coffee jug, teapot yada yada yada. Last used for my son's christening and he's 21... got a lot of it as wedding gifts. I've got at least 5 different sets of cutlery - none near £20k, but bravo @edwinbear!
I've every Harrod's Christmas Bear since 1987. I can't get my hands on 1986 and any time I've seen it, it's been mega-expensive. I also collect a certain brand of mugs and must have about 200+. I've also 200+ pair of shoes/boots/sandals and my bedroom is chaotic with clothes I have no room for. I could open a jewellers. I think I'm a little addicted to 'stuff'.
Probably my maddest purchase was as a student in 1982, living on a student grant and my Saturday job. I fell in love with a £100 pair of Renata Italian leather boots, and on impulse, I bought them. I loved those boots so much!! I don't know if they are still in my attic and what condition they would be in more than 40 years later!
Oh and I also have a lot of the Chalet School books from the 70s lurking in my roofspace. Plus Barbies, Sindys and all their rellies in a box!!