Beginner question / LOE?

I rarely do something so intelligent as to check on a project before I actually start buying things and realize I've bit off too much. I have very little experience in circuitry but I can probably handle the programming side. I wanted to check on a project idea. It looks like Arduino can do things like this but I wanted to check and see how difficult this idea would be:

I want to make a set of devices that works like this:
Point A: Arduino + IR Motion Sensor
Point B: Light

Arduino + IR motion sensor is used to activate a remote lighting object. It looks like I can easily make a motion sensor, but can I create a device where the Arduino is housed at point A and when the IR motion sensor is activated, the light at Point B is turned on? This would be a wireless light object. The idea is really simple, but I don't know what would be needed to make this a reality.

Questions:

  • Using a method of wireless communication, can I use WiFi or some sort of radio signal?

  • Would both objects need to be Arduinos or could one be a much smaller device?

Much thanks to any responses

"WiFi" as such involves too much hardware - and software.

There are modules cheaply available (eBay or Fasttech) for 433 MHz or 2.4 GHz transmission and reception, and libraries for their use. You need encoding and decoding - much like the simpler garage door controllers - to ensure the system is not tripped by interference.

All that said, you do not need an Arduino (or other microcontroller) at either end. You will also find on eBay, remote control transmitters and receivers as used for garage door controllers. Some are already configured (or can be) for one button on, one button off, so all you need to do is to provide a simple gate circuit to "press" one button when the motion sensor trips, and another when it releases (or times out).

If you do use an Arduino, you do not need something "smaller"; you use a "Pro Micro".

"LOE"? Level of Effort?