and as far as them debt collectors go just refuse to answer the security questions. they can not talk to you about anything with out you confirming your details.
"I'm unable to answer any data questions, as I have and will never discussed my personal affairs on the telephone due to security. I therefore only conduct my financial affairs in writing, so that both parties have a written and tangible record of activity in the matter. So if you can send me a letter, I will of course respond to you. Thank you for your call ... Goodbye". All said nice and polite