Having tried something similar to this in the past, I found that the business was much more sales than technology. Small businesses are very cost-conscious, and slow to adopt new technology.

It required a lot of sales up-front to land a deal, and then the willingness to pay was ridiculously low. My end realization was that, given the effort required to land a customer and the number of customers it would take to reach break-even profitability, it was basically impossible to make money on the idea.

Your idea is slightly different, so the numbers may work out for you, but I would think about how many customers you need at $27 a pop (in USD). Basically, you are going to need a cheap distribution channel that can sell thousands of subscriptions to even come close.