Look at you breaking out the Moderator kung fu!
Yeah, we can do stuff like that on threads we are involved in. But if something turns up on this thread and a mod needs to calm down the argument, I have to pass that off to another mod.
While I really would like to build my own custom multi zone security system.. there are a number of off the shelf systems that are better suited as they have done all the FCC type accepted legal / development work... One I have been looking at to replace my current (incorrectly wired one) is SimpliSafe.
There's a couple of threads in the Homestead board about do it yourself security systems. Might want to look in there. That one you linked to is kind of confusing. If you look on the features page, it says that the cell monitoring is $15 a month. But if you look on the pricing page, it says free cell. Which is it?