As Caydenn said, the price per hour is pretty bloody steep when there is no plaster on the walls.
The plasterer has a job that's much more labour intensive and wouldn't charge that much.
If it's hard for me to get the wire through a noggin, I'd rather make a hole and drill it through then patch the plaster up. We know the paint code so there's no issue to make the hole disappear again.
Have fun voiding your build warranty!
Thanks!