Wireless communication, Arduino, Raspberry Pie, Motor, LCD, Temp.

Hello Experts!!!

I want to make a project :

in which 3 boards (Let's say A, B, C)are there -

1. each one is having a temp. sensor and

2. have a motor controller i.e can control a motor (each will get a Analog reference (result of some calculations) from D to control the motor speed)

3. Have a wireless transmitter(Trans receiver)

Now one 1 board (Let's say D) is there -

1. Have to generate a analog out

2. Have a wireless Receiver (Trans receiver) i.e. will receive temp. from A, B & C

3. Have a 7 or 8" LCD display (In which all the temp. are coming and Motor Speed are coming)

 

Please suggest what is the best configuration, which modules should i use, what can be the cheapest configuration

Eagerly waiting for the reply

Thank You.