/diy/ - Do It Yourself

So the elevator in my apartment building is pretty slow, I want to make a device that can call it for me. I don't want to mess with the insides because I don't wanna come off as a terrorist and I've never soldered before so it seems risky for a first attempt.
The programming part I can handle myself probably. I was thinking about a mechanism where I use a rubber band or similar, the device will release it on demand and I'll have to prime it again every time (though I'm not sure this is viable, the button requires some force to press). How should I go about this, hardware-wise, in the cheapest way possible? I want it to be connected to my WiFi network. What do I buy?
The floor is all mine so neighbors won't complain or anything.
>pic related