Ann: Annual Report to shareholders, page-18

Got my membership a decades ago. It was not 25k back then it cheaper. I still pay the $2.5K each year but that is tax deductible, the membership too from memory but don't quote me on that ask your accountant. You need to be specific to your accountant that you are "Share trading as a business" and prove that you have enough volume of trades to make it so. It is not the amount but the volume

The ATO website is very clear on this:
https://www.ato.gov.au/General/Capital-gains-tax/Shares,-units-and-similar-investments/Shareholding-as-investor-or-share-trading-as-business-/#Sharetradingasbusiness

Correct, It makes even more sense once you hit the 0.12% brokerage fee Commsec charges for 25k+ trades...

I don't usually do trades less than 1K, Commsec will charge $20 still, but I have a way of paying only $10. I opened a Commsec trading account with a corresponding CDI account under my 4 year old daughters name

Hope that helps...