Wireless Access Point Buying Consideration

What are the factors to consider when buying a wireless access point that would be used to cover a distance of 1km?
How many access points or repeaters should be deployed to cover 50 households within the 1km diameter range to provide them internet access?
Thanks for your inputs

Hi,

You might want to see this - http://forum.mikrotik.com/t/360-basestation/49965/10

Rgds,
Mark.