In accordance with ASX requirements, your initial purchase of any particular equity securities must be at least
500 AUD worth of shares, known as a "minimum marketable parcel of shares" requirement.
CHESS-sponsored: Your account must comply with the “minimum marketable parcel of shares” requirement.
Custodian: Your initial purchase can be any amount when trading the 500 most traded stocks & ETFs, starting from 1 share.
Detailed listing: ASX500.pdf