I have an old iMac from a friend that had a dead harddrive that I was able to replace pretty cheaply and has worked fine ever since, though it's topped out at an old OS.
I got another iMac from a neighbour suspecting it may be a harddrive issue as well, which could be an easy fix.
BUT, with both of these stopping at much older OS's that don't get updates any longer and won't run more modern programs, the question came up today...
