Well, in my case, let's put that kind of request in its fair context: since at the moment I'm only offering my services on Seeking.com by a profile where there's no clear face picture of mine, it seems natural to me that a potential client asks to see my visage...!! But I'm not prepared to divulge online anything which could favour my personal identification, so, if he insists, I offer to meet outsite his Hotel just before the planned meeting (usually beside the Main Entrance) and show myself, without any obligation or compromise for him, if he doesn't like me he can refuse to go on, without any charge, not even the transportation costs.. So far nobody walked away...