The exchange/escrow can very well rule against you if you protest.
It happened to you? And what was the evidence like on both sides? In my experience if the evidence is of equal weight then it stays in dispute.It would be very possible for you to send an empty envelope (as suggested above) and it would be very possible for the seller to claim the envelope was empty when it was in fact not.
For less hassle, you can pick a reputable seller, like a pro trader, but it is not required since you only need to be responsible. Demand video from seller (before you send anything) and require seller to include footage of all aspects of the delivery and inspection (for seller's protection). Take video footage of your-self sealing cash and handing package to USPS clerk; you can use this to resolve dispute in your favor if seller does not produce video proof.
What you negotiate in a trade before you mark payment complete is a verbal contract that becomes part of the terms of the trade and seller is bound thereby.
it is highly suggested that you require nonstop video footage evidence of 1) the pick up of the package from USPS clerk, 2) opening of package, 3) counting of the money, and 4) validating the legitimacy of the notes, optionally 5) any reference number that you included with your package or proof that the seller was at a USPS facility and picked up the package from a real clerk.
Make sure that the seller picks this up at the post office and links you to that video footage as part of the trade; if seller fails then you get the escrow.
I hope this helps!
