It's better to open an Unpaid Item case when presented with a non-paying bidder or buyer. For future reference, you may do so four days after non-payment and close it another four-days after it's been opened. That gets your item back on the market in eight days. Plus, there are then consequences for the non-payer in the form of an Unpaid Item strike on their account. With a Cancel Transaction request, you are stuck waiting ten calendar days to the minute (if your non-payer goes AWOL) before the case will close automatically due to it being ignored by the buyer.
There are no consequences to the buyer for either requesting or then ignoring a Cancel Transaction request they have asked you to do. This is a source of irritation to me. Too many people buy items, don't pay, communicate once three days later to say, 'don't want it, please cancel' and then ditch. If you then open a Cancel Transaction request at their request, it means almost two weeks will have passed without the opportunity to re-list the item to someone who might actually want it.
As a rule, you are not really safe to relist an item until the Resolution Centre case is closed. It's always possible the buyer will change their mind and pay in the eleventh hour and, if you have sold it to another in the meantime, you are left at fault for not having it to send to the original buyer if you have only the one item. If you have multiples of the item, by all means, relist right away. If not, don't.
This is an area that I hope ebay will soon address. There should be consequences for buyers who make purchases and then chronically dump and ignore the cancellation requests they have asked for. It should be considered the same as a bid retraction, in my opinion. Either that, or ebay sellers should be able to take action a LOT faster than ten calendar days later if the Cancel Transaciton request that a buyer has asked for is being then ignored.
Good luck as you carry forward.
