Yup, I've thought of building that system many times myself.

May I suggest attending events put on by local community associations. Run the idea by folks you meet there, see if any will sign up on the spot (use a paper signup form to keep it really simple), if they don't immediately signup find out what their reservations are. Rinse, Lather, Repeat and you will either find out how to position the product, get an idea for a direction to pivot, or give up.

Good luck.