Starting an Email Marketing Company...do you think this is reasonable?

[ElleEsEnterprisesLLC]

Basically, I have been actively collecting email addresses from a wide variety of clientel and potential customers for over a year. I have a total of over 5,000 emails already. I am offering email marketing services to businesses that are interested in growing their business, or maintaining contact with their current clients. I would take responsibility for building their databases, maintaining them and creating and executing all correspondence with these clients....for the price of......$50 a month to start. Is this a service that you think would be of value to your company? If so, what is your company's objective? and what price would you be willing to pay for such a service? Is $50 too much? too little? All feedback is greatly appreciated!