Thinking about the things in my apartment that are older than I am: Depending on how often you wear it, classically-styled, well-made formal wear. Jewelry generally. Flatware, especially silverware. High-quality furniture. Certain books. Fine china. Winter clothes. Photographs.
In addition to all these, at my parents' house, things older than or about as old as they are: Original artwork (most wasn't bought, though; ancestors created it). My grandparents' marriage license. (I guess they didn't buy that. How about their marriage license as a buy-once item?)