Dell Computers sells what it calls "refurbished" computers on e-bay and elsewhere. I purchased one presuming that it had been "refurbished". When I received it, it kept doing quirky things and didn't work right.
I went to the Dell site and ran a diagnostic test on the computer which said that it had a defective hard drive. To me that means that it wasn't even tested before they sold it.
I checked with Dell and their cheaper replacement hard drive was about $150 at the time. When I contacted them about replacing my hard drive they said they would allow me $50 towards a new one. When I protested their response was "after all, you have a USED hard drive".
My suggestion is to NEVER purchase a refurbished computer of any kind, particularly from Dell unless you can be absolutely re-assured that you can return it if it is defective for a full refund.