Hi, I notice you have removed a section that crosses in to private property. Should the remaining section have access=private removed or have foot=yes and bicycle=yes so that they can link to other path segments.
access=*?uselang=en-GB

I have reverted this misplaced address

You have misplaced this closer to Adams St than Powers St.
It would be better to add the details to the building instead of a fence next to a footway

This area is not defined properly
relation/9592514
I am unable to know the bounds in the bottom left corner to fix it.
Can you fix the Gungahlin 792 boundary.

Hi, osmi detects a problem here
https://tools.geofabrik.de/osmi/?view=areas&lon=149.16720&lat=-35.20780&zoom=16
relation/9592514

Hi, when mapping a house, draw the outline accurately of the house itself instead of the block. Pressing Q will square the sides.

Hi, the grass multipolygon has an inner touching the outer ring at the top right corner.
https://tools.geofabrik.de/osmi/?view=areas&lon=150.73818&lat=-34.01152&zoom=19

osm.wiki/Relation:multipolygon

Hi, osmi areas detects there is a problem in the way you constructed the grass multipolygon.
https://tools.geofabrik.de/osmi/?view=areas&lon=148.02305&lat=-34.63368&zoom=17
Inner rings cannot touch the outer ring to be valid. See our wiki for multipolygon validity.

I reverted this change.

I also mapped the building and tagged as building=yes

I added office=company to the node so that the info gets rendered on the map.

Hi, if you want to map the building that the company occupies, map the bounds of the one building instead of altering the landuse tags for the whole commercial landuse block.
I have restored the landuse=commercial to the block.
If the company occupies all the building you map then you can apply the business tags to the building but on the node is also fine, and necessary if others are also based in the same building. Don't duplicate tags on both the building and node, just the one business listing is needed.

The name of the road is hyphenated in osm Southport-Nerang Road
way/579335036#map=19/-27.985538/153.339147

I deleted your coarse landuse boundary as it already mapped correctly.
way/820233155#map=18/-34.572499/150.750857

Hi, the Calderwood boundary is already mapped in osm.
relation/6076571#map=14/-34.56061/150.72797&layers=D

Hi, there has been recent discussion about changing roadway classifications on our community forum.
https://community.openstreetmap.org/t/recent-road-hierarchy-retagging-nsw-sydney/131206/4

Hi, Sadleir Street is the correct spelling. I have corrected it.

Also added a few driveways to clarify property access.

A building tag is only used to outline a building shape. The land is already tagged as landuse=residential but a polygon encompassing a larger area as well as landuse=greenfield for this block of land.
If you want it to be displayed differently you could map a surrounding fence line if it is present.