Can I remove someone that I know has me as a saved seller as I do not wish them to see the items I am selling anymore?

 you cannot prevent them from seeing what you sell all you can do is block them

http://pages.ebay.co.uk/help/sell/block_bidders.html

only way to prevent them seeing its you would be to open a second account and not tell anyone its your account

 even then some people will twig it easy

 you need new id new email address ti to same paypal account

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