By default, any member can buy from a seller. However, a seller may want to deny service to a certain BrickLink member.
Sellers have the option to stop list any buyer on the seller’s Stop List page. A stop listed buyer can no longer buy from the seller who stop listed them.
BrickLink is entirely uninvolved in a seller’s decision to stop list a buyer and cannot intervene in that decision.
When a seller stop lists a buyer, the seller can note the reason for the stop list. That reason is only viewable to the seller and cannot be seen by the stop listed buyer.
Buyers can choose to hide items from sellers who stop listed them in searches and wanted list results on the following pages: