I had a Hasselblad 500C body that I had fixed. It was the main spring controlling the mirror that went bad. I fixed it and continued to use it for several more years. I upgraded to a 500C/M body, and the old 500C sat as my backup and didn't see much use. I sold it along to someone else, who then had to make some major repairs as the air bladder that controls the rear body doors had dry-rotted and would no longer keep the doors open reliably. Were it still my camera, I probably would have fixed it myself and kept using it. The 500C body had been owned by several wedding photographers before me, so it saw heavy, regular use, and it was already 30+ years old when I bought it. And while it wasn't a failure, I did have my Rolleiflex completely overhauled after I bought it- it's another very old camera (circa 1956) that needed the shutter, film transport, and focusing worked on. $400 later (ouch), I have a camera that with reasonable care will last me another 50 years.