The buyer and the artist: Ritual purchase

[Seriy]

artcol, to take back no problem, some regret that I sold it, but I have absolutely no joy, if six months later the buyer who buys a piece of work, return it in a crumpled state, and the percentage of commission to me, too, will not be returned. A loyal customers I have, alas, not yet.
That is to say that the generally accepted norm in artbiznese not elaborated on the return?

Added after 4 minutes
Lucy, because if we take as a rule of the pack, you have to have (buy), special packaging materials and tape, so as not to trash, and wrapping paper, so as not out of the herring, folders, cardboard on the lining of thin bumlistov.