Hey Darren,
Great, another bloody interloper from the Big Smoke coming with their latte sipping, smashed avocado on toast habits to God's Country!
Enjoy and envy ya!
I 'inherited' the family farm up that way but still have several years in Shitsville Purgatory (Sydney) before the Great Escape northward.
Firstly, hope you're out of flood reach? The whole place are floodplains and swamps!
(For our American allies, the area is very similar to the Louisiana climate and landform)
As an indication, I'm slowly putting together a property report for my place as per Permie lore:
* Orientation - sun, prevailing wind intensities and storm directions, etc
* Rainfall
* Solar access
* Contour plan
* Likely position of fowl run, water tanks, shade trellises, espalier, etc
* Soil analysis - mainly profiles, not chemical composition as that can be easily changed
* Worm farms,
compost bins, shade house/nursery
* Stock animals
* The mother of all sheds
* Rehabilitation of heirloom plants
* House renovation
There's LOTS of free data available from our Federal, State and Local Government departments, Google is definitely an Australian Permies friend in that regard.
So, if I had to give you a suggestion of what to do first it's ... nothing! Just walk around and get to know the property's eccentricities, observe things, take comprehensive notes, allow for seasonal variations, make a plan, prioritise actions, then make it happen. It'll save making costly and time consuming mistakes.
For example, the first thing I've decided to do is build a very sturdy fowl run and stock it with a variety of chooks, geese, guinea fowl and turkey. They'll provide eggs, meat, manure and consume scraps - maybe even a bit of an income. The manure will kickstart the compost bins, liquid manure feed a temporary veggie garden, old fruit trees, and pasture.
Everyone has their own priorities, good luck in determining yours.
Above all, have fun!