Yes, use 4 wire "quad" for all the motions and contacts and keypads. Quad is the "old" 2 pair telephone wire- red,green,black,yellow.
Run home runs from each back to the panel location, my alarm supply house has quad in many different jacket colors so you can color code by floors, areas etc. Leave plenty of slack so the alarm guy can do whatever he wants.
I should add that you might want to check with him first for the best locations for the motions. Always new stuff and some ceiling PIR's now can take the place of wall mounted ones.
[This message has been edited by hbiss (edited 02-02-2005).]