If you’re going to start with a common statement such as ‘Your call is important to us’ and the other statements you have heard, your prospects are going to walk away.
Voicemails need to maintain a professional consistency that’s aligned with the entity it’s representing. That said, the structure can vary depending on the situation. There’s no template set in stone. In fact, trite and generic should be off the table. The goal should be a balance of uniqueness and practicality.

“Hello ___. This is ______ from _________. I’m calling because you requested information through [vendor] about [address of house]. I’m available right now to answer questions. I found a couple of other homes near the one you’re interested in, and they are similarly priced. Do you want to talk tonight? You can call or text me at ___________. I look forward to speaking with you and answering any questions. Again my number is ___________. Thank you!"
You have reached the , Strategic Air Command Nuclear Missile Storage Facility. We are unable to come to the phone right now. At the tone, please leave your name, number and target or list of targets and we’ll launch as soon as we can. And have a nice day.