Mini robots with bluetooth

Hi,

I am new to Robotics, I am trying to build 10 mini robots with bluetooth, so they can communicate with each other. I read somewhere that there is a limit 7 max.

I guess I need a chasis, motor, bluetooth card, also an electrical board. Anyone could suggest the parts that I need to build a mini robots?

Thanks,
A beginner

My robotic vacuum cleaner connect with its power source using blue tooth technology, you can take a look at it here to get some idea. robotstofzuiger. There are the robots designed to clean homes but they rely on smart communication system in order to do their job.