Thank you for your answers but that just shows how new I am. I was actually referring to the hardware cost (switches, etc..) .
I understsand I would need one switch per room, but what else would I be needing?
Thanks
With insteon you are likely going to need two accesspoints to bridge the signals across the wiring in you home, IF you don't buy the dual-band switches which are more expensive. You will also need some sort of computer interface if you want to access them from a PC. That could be a PLM+Software. Most people using Insteon like the Universal Devices ISY which is a small controller that comes with a PLM and has a web interface.
So...
1 Switchlinc Dimmer or Icon Dimmer for dimmable lights
1 Switchlinc Relay or Icon relay for fans, florescent lights, etc
Determine if you want any keypads for scene control (optional, substitue in place of a dimmer or relay switch)
2 access points (or change dimmers to dual band)
Optional PC Control (if doing dual band, make sure to purchase the dual-band PLM option with these):
ISY
Insteon Central Controller
Vera + PLM
PLM + Software (CQC, Homeseer, Houselinc, Powerhome, Premise?, etc)
The forum moderators will probably frown on people posting prices, so you will probably need to go price these out on Automated Outlet (highly recommended) or Smarthome. UPB and Zwave will be slightly differrent, but follow the same premise, dimmers, relay switches, keypads, and some form of PC control. For UPB you likely need a signal brigde too like insteon. For Zwave, no bridge is needed since it is wireless. Alternatively you could probably call or email Automated Outlet and ask these questions and get estimates.
I would estimate at 1 switch per room, 8 rooms you are talking around $600+ for Insteon. If you go with all Icons you might save $100.