When I was young, I used to call friend's Mums & Dads and my adult neighbours Auntie and Uncle etc, then their name, so for instance Auntie Pam and the more elderly neighbours (pensioner age) Mrs. or Mr. then their surname. Now I'm adult, I've found that my own neighbours prefer me calling them by their first names as Mrs. or Mr. seems a bit too formal and I guess a little less friendly.
