We have a café & need to be pci compliant for credit cards, 4 computers & guest access.
There is actually no answer to your question as:
- Signal will attenuate (reduce) as it reacts with the environment (passes through walls, reflects off metal surfaces, etc.)
- Each environment is different. Your cafe will have a different layout and construction to your house, for example.
- Each wireless client (laptop, smartphone, etc) will detect a different signal strength at the same location so, for example, how far a laptop can be from the BR200 before it disconnects is different to how far an iPad 3 can be, which is different to how far a Samsung Galaxy S5 can be and so on...