Due to the high prices in Broome, locals have been selling up, taking the cash and moving to Derby to live on their profits. End result is a steep rise in prices on the Derby market. have most likely hit its peak sans any major notification.
They are making land available a bit out of town central, should be a result there (see the DPI land release site).
I have a couple of reservations re Derby -
Global warming may or may not be coming, but I have seen the highest tides ever in Broome. Derby would be no different. Unfortunately, Derby is only about 1 metre above sea level max, and most of the town is about 300mm above - so what happens when sea level rises?
Derby town airport is built on marsh land, gravelled over. Ansett stopped flying in there because the runways were 'humping' up due to BaE 146 landings; it was too expensive to rebuild the runways to start again. Hence the use of the Curtin Air Base strip, 42 km out of town. There is a thrice weekly service Perth - Derby direct by a smaller regional airline, using a pure jet into Curtin. Long and short of it is, the air traffic problem will not be solved easily, so travel ex Derby to the rest of Oz and the world in general is limited and costly.
Port facilities in Derby are virtually non existant, and even if refurbished, are tide limited (the jetty dries out). Short of starting again with a completely new facility at Black Rock / Pt Torment, Broome will remain the main supply port for all gas field developement.
Entry and exit from King Sound is a nightmare, and dependant on tides.
I would seriously keep an eye on what happens at Cockatoo and Koolan Is - they are also a prime site for a processing plant, with good sea access. Iron ore mining at Koolan is again underway, but is finite in life span.
Some Resource Companies speak with forked tongues
There are Diamond mines, Zinc mines etc. in the hinterland but do your DD