Hi Flying Dog
last august i was in Darwin for work meetings and my wife and i relocated a 4 berth motorhome from Darwin to Melboune via Adelaide (to catch up with my son ) it cost $5 per day for the vehicle plus the fuel ,they re embursed $465 for fuel in Melbourne,they give you 8 days to get there lots of driving,some parts are boring ,Alice is a great place to visit ,at one place in the bush the road widened and no trees posts etc BUT the Piano lines in the road ,must be the RFDS emergency landing spot ,we have also relocated from Brisbane to Melbourne.the link is