Setting Up Wireless Home Network

We are building an g+4 story apartment for residential purpose. I wanna setup an wireless network for internet, file sharing, multiplayer games n for other purpose. I have few que regarding it.

1. Is it possible to set up an wireless network for g+4 story building? What is the coverage of an wireless router or something like that?

2. What would be approx. cost for building tis wireless network?

3. Which 1 wud be best, Wired r wireless?

4. Is it possible to connect TV with computer with this wireless network? or is there a wifi featured TV?


Thanks in advance