If you're not in control of the selling situation you can't service your customer properly. In this business, your time is your money. These people are professionals. Their time is important. I cannot emphasize this enough.
Time is our most valued commodity.
You can't buy it beg, steal, or borrow it. Memorize the following lines to explain to the consumer how you work. I know how busy you both are. This last line is telling them why you work by appointment. When I started in this business it never occurred to me to work by appointment.