Conducting extra research on your prospects before you call them is always a good idea. This script from Mike Brooks is a great example of how you can use this additional information in your sales voicemails.
The above section details types of phrasing to avoid; however, it doesn’t detail what users should NOT say on their greeting. Though this is a bit loaded, as there are hundreds of combinations of things one shouldn’t say, there are some key components users should ALWAYS avoid. a. Forget About Slang: You should strive to be as professional and welcoming as possible in your greeting. While this may steer you towards using slang, in an attempt to make callers comfortable, it’ll most likely work against you. As a professional, your demeanor, tone, and speech should be clear cut and well articulated. Using slang undercuts this and works against you. b. Don’t Even Think About Profanity: This is a no-brainer. Never, under any circumstances, curse in your greeting EVER! c. Keep Your Sentences Clean, Don’t Ramble: Introduce yourself and give your caller specific direction. Avoid long diatribes detailing tangent thoughts. Keep it simple and quick. d. Always Return Your Calls: It’s important for callers to feel they are valued. Nothing dissolves this quicker than a greeting that doesn’t stress this. For example, “I’ll call you when I can,” “If I don’t return your call, please call back”—these phrases are terrible and completely destroy any good will you may have with a caller.

Voicemail essentials: Identify yourself because you need to reassure the client that they have called the correct number. Clients will be a lot less likely to leave a message if they wonder who will get it. Use a warm friendly voice to say something like, “You have reached xxxx, licensed mental health counselor.”
People around us can need help at any time of the day. Many a time friends, family, boss, colleagues, relatives, and acquaintances need to inform us of something important at odd hours. Some may know when to call you and some of them won’t. In cases where you are not accessible, leaving a simple voicemail on your phone can ease their worry.