Never use voicemail as a way to avoid speaking with someone. It doesn't help, and a person would have to be terminally dense not to figure out your game. If you must call when you know the other person isn't available, say, "I know you won't be able to take the call now, but I wanted to let you know that..."
No matter what, speak positively about yourself and the services you provide. The first mortgage call is just as important as ever. To remain relevant, mortgage originators must provide value. So, that first voicemail is your golden opportunity to do so!

Here I'm referring to lines such as "Please call me back" or "I'll check in again on X date." Because they're generic, these asks don't increase the buyer's feeling of responsibility. Instead, I suggest posing your specific question and ending the call there.
Yes, you can make an email personalized, too. But voicemail is already much more personal than an email, and your level of customization should rise to meet that. Plus, if you’ve spoken with the contact in the past, there’s an even bigger opportunity to build on what you already know and cater the message to them.