I just say "I am not interested but thank you for calling." and slam the receiver down. Political calls I just say "I do not discuss politics over the phone" and hang up.
You think because you have an unlisted number you are exempt from these calls, or if you are on the no call list no one will call - au contraire!!!!! It is an automated dialing - they will call 000-000-0001 and then it goes on to 000-000-0002. They'll getcha!!!!!!!!! So I am just polite and then slam the phone down. I do have a whistle if that becomes necessary, but I just don't give them a chance to talk. Edie