Caution when purchasing used Laptop Hard Drives

A word of extreme caution when purchasing used hard drives. The hard drive is the most critical piece of hardware in any geputer. It is the brain and storage of the entire system.
I have fell victim of purchasing what was to be Tested / Formatted drives and 70 percent of the time the hard drive failed the initial diagnostic check I run on every hard drive or the advance test where sectors were repaired by previous software. If one or more sectors are bad then it is a sure bet more are to follow. I since have sworn off buying used hard drives, If you think you are saving a dollar then think again when all that data is gone or you spend hundreds of hours or cashrecovering lost data. Plain and simple it is not woth the savings. One more thing to consider 99 percent of the sellers of used hard drives will not refund all the shipping especially the cost to return it, most will charge more than actual shipping charges to cover any returns and there again you loose money. The only way I regemend buying used hard drive it to ask the seller what he will refund, I have yet to find one that will refund everything. Its not to say that they don't exist I just never found one.
What ever you do Never ever purchase hard drives that have the description of Not Tested Sold as is, I see many many feedbacks where the drives never performed. It is the biggest gambleI have seen to date on okay. Almost as bad as the mystery box.