If the best alternative to using your app is a free Google Voice number in your area code (and not $20/month to Time Warner), I don't think $10/month is something I would pay. I'd either find a way to make the pricing work, or (as suggested above) find a way to sell to apartment complexes at large.
For the longest time, the homepage was Rails' index.html. It was so hard for me to bang out those few paragraphs.