I might just go for cctv - some packages out there go for 1k+ for 4 cams/ mic, pull wires, video box recording, android/iphone viewing, pay more for IR, and no PTZ.
In case if you are keen, Challenger FUNAN got DVR which you can DIY, $599 with 500GB HDD. Saw it when I was there.
It comes with 4 x IR Dome Cameras at 600TVL, 18metre cable should be more than enough for a normal home.
Can view over iphone/android.