First, I got the information about the meeting. I will meet you in the building lobby at 2:30. See you then. You might want to repeat your number at the end of your message. That would sound like, "Again, my number is xxx-xxxx should you need it." Then just hang up. There is nothing rude about that; you don't need to say good-bye, since there was no conversation.
You should also research other people in the prospect’s organization. Selecting the right people, such as the prospect’s manager or department head, facilitates the ability to build rapport and adds a sense of urgency when you mention them in the voicemail.

State your number right after your name. Many people wait until the very end of the message to state their number. This will irritate the receiver of your message because if he doesn’t get it down, he then has to sit through the whole damn message again to hear it repeated.
While missed calls aren’t ideal, you can let your caller know you’re still there for them by having a great voicemail greeting. The best business voicemail greetings let your customers (and potential customers) know why you’re not available and how they can best get in contact with your business. They are also short and to the point. You usually want to keep your greeting between 6 and 24 seconds long so callers don’t hang up halfway through.