Not becoming pushy or rude is important since the decision maker will be more apt to return the call of someone who is persistent and professional. They may even call to tell you they are not interested, but your goal is to get a response, so think of ‘no’ as a win, too. They have just allowed you to update your list by removing and replacing them with a better-suited customer.
During your follow-up call, if you can only leave a voice message, wait three days and then call them back. Tell them you left a message before (if you get their voicemail again) and you wanted to make sure they got your message, as well as how they can reach you again. An email address may be another beneficial tool to give to the potential customer in addition to your contact number, so they can reach you at their convenience.
–Aaron Montgomery, 2 Regular Guys, MontCo Consulting