1) What kind of software is best used to send out massive email to multiple emails at once? How does this work, let's say you have a client who signed up but no longer wants to receive your email, how can they unsubscribe? Is this a 3rd party service that used or do you manually remove them?
2) Most emails providers nowadays (Gmail, Hotmail, Yahoo, Etc) have spam filters that detect certain emails (not sure the logic behind it). How can you make sure your email doesn't go into the spam folder and is sent directly to the inbox?