As previusly stated, you have a set number of listings that you are permitted per month.
Expired or sold, that is all you can list until the next month.
As you build up a history of succesfully completed transactions, shipping within your handling time, packing well, item as described, your limits will gradually be raised. I believe initially the time is three months if you are new before they consider raising these limits.
Handle your selling responsibilities well and you will be successful and have your limits raised.
In the meantime, you can research Ebay policies so you know how Buyer protection works, what your responsibilities are, and listing and selling policies as well. Reading this Board is a great source of info as is the Help Index. Know how to properly create a listing, clear pictures, accurate and complete description that describes any damage, title maximized for best search results, packing well to avoid damage, shipping within your stated handling time by the method you noted in the listing.
You cannot ask the buyer for more money post sale.
