Uneeb629
Newbie level 2
For your guidance I suggest, you use a cheap RF module working at 433MHz frequency, if you want I quality use HC-12, and use a any PIC avaliable to make it cheaper I prefer use PIC16 or PIC18 C series because they are 1 time programmable and are very cheap. Then for sensing you can use already built sensors or you can use reed switches to make a sensor. Making a sensor depends upon your available resources.