Spock is a shitty app. Out of my 2 transactions, both failed. As a seller, you are absolutely not protected, its all about the buyers. One of my "clients" never paid and was legally binded to but Spock only sent them a cordial message (unanswered of course) "threatening" to delete their account. Big f****ing deal. I never got my 120£ and the account wasnt closed. On another transaction as a seller, which I honoured, I received a 2 star rating out of 5 for no reason after communicating at all stages with the buyer and even paying postal fees from my pocket without invoicing. Just forget spock and go on ebay, unless you plan to scam sellers and have them get all the troubles for your dishonnesty.