The only buyer requirement that can specifically be selected on the Auctiva lister page is "Require Immediate Payment". In order to add other buyer requirements, please specify them in your eBay selling preferences, and they will be applied to the listings that you create via Auctiva.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .