I have ADT and they didn't charge me for the equipment or for installation, but the monthly was about 45.00. My main goal was basically to use them through the 2 year contract, so I can get the equipment and then switch to alarmrelay.com for $8.95. I went this route because I didn't want to deal with buying and installing the equipment, but had I known how easy it was, I would have just bought a system and save a few hundred dollars. The installer that came by basically mounted the keypad, plugged it in, stuck the sensors with double sided tape, and programmed it, literally a 30 minute job. The system he installed was this one:
http://www.homesecuritystore.com/p-1489-lynxr2-kt100-honeywell-lynx-plus-wireless-alarm-system.aspx
Everything is contained in the keypad, the alarm brains, siren, phone module etc. You may need to add the GSM module if you don't have a landline.
If you're comfortable with tinkering with the system, I would suggest just buying your own equipment and pay much less for monitoring through alarmrelay.com or smarthome.com.
http://www.homesecuritystore.com/p-1489-lynxr2-kt100-honeywell-lynx-plus-wireless-alarm-system.aspx
Everything is contained in the keypad, the alarm brains, siren, phone module etc. You may need to add the GSM module if you don't have a landline.
If you're comfortable with tinkering with the system, I would suggest just buying your own equipment and pay much less for monitoring through alarmrelay.com or smarthome.com.