Since I started telling buyers that I log serial numbers for every item I sell, though, a surprising number of them started closing their own cases.
The buyer filed a complaint that the printer wasn't new. I responded with "Of course it's not, look at the title & description." Ebay made us pay for them to ship it back and refund the money.
When we got it back there were 2,000 more pages printed on it.
I'll NEVER do any business through ebay. You are either braver then I or have a higher tolerance for bullshit then I do.
Fortunately, most people do the right thing and with the mitigation strategies we have in place we lose only around 0.5% of revenue to (suspected) fraud.
eBay's ~10% processing fee makes a much, much bigger dent in our bottom line.
When I worked retail, we used to get people buying cameras or lenses and using them for a weekend, then returning them under the 7-day "no quibble" refund policy.
It wasn't uncommon for a camera or lens to come back with 10,000 shots taken. Best we could do with them is clean them up and sell them on as refurbished. A few went back to the manufacturer and came back as "factory refurbished".