“Marks on the underside”


I sold a piece of equipment on eBay and described it as having only slight almost invisible blemishes.
The buyer requested to return it to me because of “marks on the underside.”
I granted the return without delay.
Now I’m having second thoughts.  My question is, do marks on the underside which obviously are not visible when in normal use, count as a valid reason for return?

128x128rvpiano
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I would never complain about marks on the underside.  That's a BS move by the seller.   The seller should be embarrassed for even bringing it up, let alone requesting a return.
"Perspicacity"?     That buyer seems much more shrewlike, than shrewd!                                                                               ".....not worth the hassle."    +1
Picky picky picky.    Since when is a buyer a seller? 
Sounds like the buyer changed his mind and grasped at straws.
Who is to say the inconsequential marks weren't created during unboxing?
Sympathies to you, rv.