to the refund! she said in the listing that she had bought it by mistake, so perhaps she didnt even know what nappy it was herself!
She really should have paid the return postage, as it was a fault on her part (it is her responsibility to know what she is selling, and if she sells it wrong, its still her responsibility!) If you had opened a dispute you would have got all postage costs back. Its fine to state that she wont pay return postage but with any sale that is faulty or misleading, you have a right to have return postage paid. Still, I know what you mean, if she was so nice about it then its harder to begrude paying the postage