I started at a big city bike Co-op a year ago. Volunteers receive a substantial discount on used donated gear. I was initially concerned that this would cause my (large) horde of bike stuff to balloon. But the opposite has been the case. Deep down in my psyche: I now realize that so much stuff is passing through my hands weekly, that there is really no point in putting it into my personal inventory. Or even having much of a personal inventory.
Maybe once a week I see a part that tweaks my interest, but unless it is labeled: "Record" or "Dura Ace", I am no longer interested.
Actually my stash is getting smaller, as my riding cronies and I have donated hundreds of pounds of surplus alu seatposts, stems, cranksets, etc. Again, if it is made of carbon and has titanium bolts, it tweaks my interest. If it is made out of steel: direct to the trash.
Occasionally, something comes along that could be critical for spare parts. A rare high-end part that could be a lifesaver for someone.
Such as vintage Campagnolo Shamal wheels. Or Campagnolo 116 bolt-circle chainrings. Or old metal Simplex derailleur parts. Or Magura hydraulic rim brakes. Suntour XC Pro derailleurs. Etc. But otherwise, not much now motivates my hording urge.