Seen an interesting scam. Vendor claims users FE based on death in family with promise of refund/reship. User X and User Y both pay the vendor. $100 and 250$. The vendor refunds the 100$ after 5 days of no show while claiming reship to the $250. He has used part of the $250 to payback to 100$. Scammer has $150 profit and waits for a listing order of 500$ to be FE by the next victim. Uses 250$ of the $500 to pay back the original victim.
Now he has $250 profit and can either run off or continue with bigger listings to pay back smaller orders while still making money out of originally $0 invested.
You're pretty good with quick maths.