3 Day E-mails:

E-mail 1 (problem): Write an E-mail that defines a problem most Internet Marketers face on building their list (don't talk about List Building Hub yet).

E-mail 2 (solution): Begin with reminding them about the problem in the previous E-mail, then unleash the solution by specifying the List Building Hub product and how it could change their lives. I would highly recommend that you offer a bonus from your side.

E-mail 3 (Scarcity and urgency): In this final E-mail, outline that the prices will rise with ever sale and the time is limited for the product to stay live. You could also say that your bonus will be available for a limited time or on a specific number of sales as this will increase scarcity and urgency for the customers.