Nothing quite so vicious as an artificially intelligent cyborg sentry when the guy in the basement keeps tripping its breaker...
I have made it to the forums
I can help with the hardware aspect of this but not sure about the networking.
Take a look at this custom firmware for routers it supports vpn and vlan on the cheep.
http://www.dd-wrt.com/wiki/index.php/Configuration_HOWTOs