I have a Moto G which it's model is XT1032. At home, I am receiving terrible WiFi signal.
My box is on the first floor, and I'm on the second floor. My relative has the Moto G XT10... (Different model, but looks same) and the WiFi is fine and strong. Same with my other devices.
The stock version was KitKat 4.4.4 and the WiFi version was still bad.
I am using lollipop 5. Just 2 weeks ago the WiFi signal upstairs was good but now it's rotten. It was bad before then good then bad.