I think you'll find the size of the market, measured by number of customers, to be much smaller than you think. I say this because your pricing seems very low. This is obviously a very comprehensive solution and complex software. The individual components from 3rd parties would be much more expensive if they were used separately, (e.g. MailChimp, CRM, etc.) so I think you should price based on what the cost of all the items would be.<p>Another commenter said 4x, I'd say 10x plus an upfront fee.<p>However, I could be wrong, please correct me if you've done trials and found this to be the best price :)