As a Realtor, when working with public it's always good to remember to call the people we set appointments with. I have learned, that calling one hour ahead makes good practice. I can't tell you how many times , when I didn't call my appointments, they either said "they forgot" or "didn't have my number to call me to change "or they simply couldn't make it; so chasing after somebody who ain't there is a waist of time and time is money, Don't waste time not calling and you'll avoid a real loss of time and gas and what else might come of it, business .