Local Area Network (in short LAN) is a simple networking technology that allows two or more computers to get connected with the purpose of data sharing and communicating. The average cost of setting up LAN depends on several factors including its purpose. Other factors include infrastructure and the number of computers that it will connect. The cost for setting up a LAN for two computers would be approximately $75-$85. It will cost much more for bigger infrastructures as used in schools and offices.