He's got a giant smile which is what he needs to have, and he's also got his head bow slightly forward which is very important for displaying submissiveness, very useful for a salesman.
Lord Beric paid no heed to her outburst. " My lady, " he said with weary courtesy, " would you know your grandfather's brother by sight? Ser Brynden Tully, called the Blackfish? Would he know you, perchance" ?