Just to help other members here on salehoo that if you believe an (individual or company) is committing fraud, by all means, please file a complain at Link hidden: Login to view and show this fraudster a taste of their own medicine!
I just file a complain against my customer who just filed a chargeback for an Unauthorized Payment with their credit card issuer.
Make sure to keep all copies of evidence to show if they require you to provide it.
I'm not just going to let paypal solve the problem on my behalf. The fact that this individual is cheating me $875, I think I have all the right to file a complain against him/her.