I've heard of people doing this informally with the consent of the site supervisor, but I can also imagine some supervisors knocking it back. With builders it seems to vary, and some won't allow it.
Has anyone managed to negotiate getting your own licenced cabler to run cables for alarm etc during a build?
As a licenced data cabler, best I could do was to get the builders sparky to install cable I've provided, to my specifications, at a cost of around $25 per point. Me to terminate after handover. My points are a combination of CAT6, siamese RG6 for foxtel and RG6 for TV to about 25 locations.
Plus also had agreement for them to install C-bus, me providing all hardware, them running and terminating power cables and me c-bus cables after handover. Again about $25 per switch location for labour, plus a bit extra for the switchboard work.
So end result still $10-15k cheaper than having them do the lot, but still a few thousand more than me and my sparky mate doing the lot which would have been my preference.