Hi Tom,
To change a single bathroom cupboard (middle cupboard of ensuite) to three drawers cost me $415 for comparison. I didn't put in any additional kitchen cupboards, but I've been told it is roughly $1,000 per meter of additional cupboards (presumed 600-650mm deep). Again, different builder.
I drove out there again yesterday and there's multiple slabs sitting there, a couple of 'For Sale' signs, I think just the one 'Sold' and there were two slabs being poured.