Feedback Farming?
Got an order in, then a cancel 17 minutes later. Okay, it happens. OTOH I've had 5 near-immediate cancel requests in the last 48 hours vs. usually I get a couple a month. All for my cheaper items.
Go to check out user's 'feedback left for others' (i.e. chance to block if he's a bad apple). While I'm there, I notice he's got 3 feedbacks left by other sellers -after- mine (mine was left automatically when he paid).
I think I'm going back to auto-feedback after they leave me feedback vs. after they pay.
I'm also about ready to start making them wait for the cancel until the last possible moment - like right up to my shipping deadline. It's little-enough I can do, but at least make 'em wait to get their money back/sweat it a bit. Enough's enough.