A customer came in today with a Niihau shell necklace she was interested in selling. We, of course, were interested in buying.
Niihau shell jewelry is particularly tricky because without documentation there is no direct way to tell whether it is authentic. Fortunately, she had retained the Certificate of Authenticity that came with the necklace when she bought it.
Certificates can be copied, however, so a sales receipt helps add value. The more documentation , the better. A sales receipt, by itself, proves little, but a collection of papers for an item adds value. This is also true of designer bags and similar items.
The receipt might seem like clutter, but if you paid hundreds of dollars for an item, and someday you might want to sell it (or use it to raise a pawn loan), that slip of paper might add many dollars to the amount you realize.