I get fixated on collecting things I like. Whether it be useful things like tools, or just collectable things like toys or cards, or even books and media. The fun part is organizing and reorganizing them, and listing them off in my head if I'm not there to see them. The listing and organizing gets very repetive, but it's somehow comforting to do. I have special boxes, and backpacks for almost everything. My mom told me when I was a toddler, I used to have an old camera case that my grandpa gave me which I used to fill with all my favorite toys. I would take them out and put them back in, and I would carry it around everywhere, very much like I do with my backpack now. I put "useful" things in it instead of toys, but the pattern is the same.
I get very disturbed if I lose something I really like, and sometimes obsessively look for it, or at least something to replace it with. But if there was a fire or something, the first things I would save would be my family and pets. I would be much more depressed if I lost a family member or even a pet over all my favorite items.