Buying a second hand HDD

There's no way for me to tell if the scan is actually for the drive you will get. The best you could probably do is maybe a 7 day DOA warranty to make sure the drive works when you get it. Even if this is the scan, and the drive is perfectly fine right now, it could still die in a month, There just isn't any way to tell. You have to weigh the risk against the cost of a new drive with a warranty.