I would need ONE router and multiple Wireless Access Points (WAP).
No one can tell you how many WAPs you'll need since such is dependant on how much coverage a WAP gets in YOUR building.
Bob
Hi Friends
I wanted to know that how many routers should i hav to install a wirless network
if i hav to connect two buildings network how much routers shud i use
can any bosy plz guide me

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic