Hello, my name is George Bouris.
Although I can develop it using a R-Pi, I think I have a better proposal.
It is based on the ESP8266 WiFi module. It is very cheap (street price <$7) and incorporates a powerful microcontroller (32bit/80MHz) along with a WiFi module.
Consider the reduction of the cost, because of the much cheaper hardware and the simplified installation - no need for ethernet cable etc.
For the remote operation, it will poll every few seconds a web service running on your server to get the remote commands.
Furthermore, you can use static IPs or a dyndns account (many routers support its update), allowing the push of the commands directly to the ESP8266 (no need for polling).
Regarding the monitoring of the power consumption, it can be provided, just needs more hardware and software, meaning more expensive development.
If you like the idea, I will develop a prototype, install the WEB part on my development server and give you access to test it. I will, also, design the PCB.