Here's how we handle it at our house:
"You have reached the home of ______ and ______ Smith, and the home of _______'s Stampin' Up! business. Please leave your name, number, and message, and we'll return your call as soon as we can."
Just before and during Sell-A-Bration, I also have a short blurb like:
Right now, any order of $50 or more qualifies for a free stamp set!
of course, today you could add a blurb about the free calendar.