What a manager and a publicist do, what they usually cost, your rights in NSW, and who takes approaches from independent acts. Booking agents have their own page.
Source: Arts Law and Simpsons Solicitors, management agreement fact sheet.
Source: AMIN legal pack, free from Arts Law and Simpsons Solicitors.
Source: NSW Government, entertainment industry managerial agreement checklist.
The Association of Artist Managers keeps a public list of its members. Few Sydney management companies say how to approach them. These do.
Some companies that call themselves artist development sell masterclasses, mentoring or release packages. That is a service you pay for up front, which is a different arrangement from a manager on commission.
Most publicists quote per campaign. These publish their prices.
The Sound NSW Recording, Content and Promotion grants can pay for publicity on a second or later release. Rounds are listed on the Grants page.
Source: Spotify, third-party services that guarantee streams.