What's the most expensive thing you've come to own that you've never gotten to fully use?

My camera (Nikon Z6) has a lot of features I never use and probably never will. Bit it's still an amazing camera that I can use to take photos with that I couldn't with other Nikon cameras I could afford. So it doesn't matter if it has a weird feature I don't use when I regularly make use of a feature it does so well. Paired with an old 70-200 2.8 I have taken a lot of photos I would have previously not have dreamed possible with my older camera setups.