I've had a few of those issues thru the years. Someone does a buy it now, pays, and right before I ship it they request a cancel for one reason or another. I've always just cancelled it and blocked the bidder. One time I sold an rifle scope box, just the box, ad clearly stated that it was just the box. Bidder bought and paid for it, than must read the ad and said he no longer wanted a empty box, Than why did you buy it? I've learnt thru selling stuff online thru fb, ebay, etc, ALOT of people don't read ads in full. Anytime a bidder asks to request to cancel, I just cancel. Unfortunately with ebay if the buyer gets an item and they don't want it, or it isn't up to their specs, etc they can file a claim and you as a seller would have to refund, so not only are you out of the cost of shipping, but no you no longer have the item. One time I did sell a tail light, shipped it, about a month later buyer ask for a refund because their kid supposely bought it. They filed a claim, I nicely stated they bought the item I shipped it and than a month later they request a refund? Their request for a refund was declined by ebay thankfully.