Once your item is listed, you can monitor it in My eBay. If you find you need to change the listing - for example, you've learned something new about the item that you want to share with potential buyers - you can revise the listing easily from My eBay.
There are some limitations to revising your listing., depending on time left before the listing ends and whether you have received any bids or sales. You cannot change the listing format.

From the Items I'm Selling section in My eBay, click the pulldown menu in the Action column. You'll see options that let you modify your listing, such as Revise and Add to Description. Click on one of these to change your listing.
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