Zero feedback / brand-new account
Signal: A buyer has zero feedback or a newly created account.
What it usually means: Not a red flag on its own. Everyone starts at zero, and I don't cancel just for this.
Action: I slow down and look for the stack: item value, account age, payment behavior, address details, and whether the buyer responds normally. If I do cancel, I delist the item for a while so the buyer cannot just make a new account and re-buy.
When it escalates: It becomes a cancel decision when it stacks with other red flags, or when the item value clearly outweighs the cost of a possible negative feedback.
Official eBay policy
If a cancellation leads to feedback, eBay lists address-problem cancellations and post-payment change requests among cases that may qualify for removal through Seller Help.
Read the eBay reference