Question is, how do you sell such a service or actually, how do you IMPLEMENT it? Their site might be an html site or it could be a Wordpress or Jomla or anything else. They might also have their own web designer or that one fell by the wayside and the business owner might not have any access to the administrative area of the site or simply do not have a password to it.
Saying you sign them up for Aweber and charge them x amount per month is too general of an answer, I need specifics and I would like to see a discussion how others are doing it, best method to implement, to sell and what to charge and your success rate, if at all possible.
Thank you in advance, Eva