I love using Calendly. I am a High School Counselor. Parents and students need an easy way to be able to make an appointment with me. Calendly interfaces with my own calendar and only gives appointment times that are not already filled. I've been using it for 2 years. It only took a short while to set up my work hours, and I placed the link in the signature of my email. I don't have to block off time in Calendly. As long a I block it off on my calendar, a person can't make an appointment during that time. When people make appointments, they will show up on my Google calendar. It shows their email address, so if iI have to reschedule, I can easily do that.