The service and equipment would be free. So Kay would need half a million dollars to install with no return based on your calculation. It is not a money maker sorry to burst your bubble.
We have no idea what the revenues could be for studentconnect, everything is based on unproven advertising fees. Until we see if kay can sell ads for the system, how much people will pay, and how many ads sell, it's a guess. My guess is he will lose money.
Calculate that the cost of each of the units with the monitoring and software adjustments could be at least $5K each.