I just sold an item on eBay and always state in my listings that payment is DUE within 3 days of auction's end. I message the buyer and she tells me that she is waiting for an overdue payment from something SHE sold on eBay. If she doesn't receive the payment, I'd have to wait for the end of the week for her paycheck to clear. I know the protocol for filing a NPB is 7 days, right? I think my 3 day rule is reasonable! Why do people bid when they don't have the funds to pay?! I don't understand. I always pay instantly.