my futon mattress. got it close to 20 years ago, moved with it 4 times now - it's a custom size, 6' wide, 7' long, 6" thick. $400 when I got it.

my computer table. it's a handmedown from my folks, but growing up it was in the basement, I used to do chemistry experiments on it. it's got to be 40+ years old and the top has been replaced twice now but the drawers in it are super sturdy, as are the table's legs.

my kitchen cookware set - got it about 15 years ago, All-Clad brand. stuff is solid, I use it daily, and unlike some other stuff I've purchased since then hasnt broken, fallen apart, or dented. was like $500 or so.

electronics related? I have two laptops that have stood the test of time - an hp 9480m, got it in... 2013 I think, still works fine though its starting to develop some wear on the ports - might have to replace it in a few years. also a lenovo t470, got that in 2018 I think? its solid, really great platform, that's my main laptop.