How to organize a siren with local network control?

Question

Do it yourself

There is an office and a warehouse (let's say the distance is 1500 meters) united in a local network.
It is necessary to make it so that when you press a button (or something) in the office, a siren in the warehouse starts screaming loudly and blinking, let's say a flasher, like on a car.
The option with a cell phone and a connected speaker is not suitable.
So far, the idea has only come to mind to build a Raspberry-type mini-pc into the column, deploy a web server there, make a site on it with one button that would turn on the alarm.
Can you please tell me if there is an easier way to do this?
The connection of the "yelling" device to the local network is preferably via WiFi.

Answer 1

Arduino UNO (6$) + network module (though wired) - 3$ + relay module 1$ + your siren / flasher. There are a lot of descriptions of how to manage this stuff over the network on the internet, search for the ENC28J60 key.