My feeling is that all custies should have all your contact details (name/address/phone/mobile/e-mail etc etc) What have you got to hide? One of my sales pitches goes like: if you had a window cleaner and all you knew about him was his first name and mobile number, and he had an accident on your property and did some damage, how would you find out who he really is so you can make a claim? We are completely up-front, we have nothing to hide so you can have complete confidence in us.