You can not close your selling account if you still owe or are owed money.
While listing is free, listing options upgrades and selling are not.
If you list an item and use listing options that have fees, you owe eBay those fees whether or not your listing sells. These fees can get pricey. For example, a Reserve of $1000 will cost you $75 whether or not the listing sells.
If your listing sells, but the buyer doesn't pay, you have to file and close the Unpaid Item dispute (or file and complete a cancellation) to get the 10% winning price Final Value Fee removed from your eBay account before your end of month invoice is issued.
