The ACCC is the regulating body. It may take action against a business if it sees fit, to enforce the provisions of legislation, which could result in fines or other measures.
Each state has its own version of fair trading legislation, and a department that can help (up to a point), if you can’t resolve with the business. They generally provide phone advice.
For some matters, e.g. financial services such as insurance, there’s an ombudsman.
For individual consumer issues, if you can’t negotiate a reasonable solution with the business, eventually, your options are to take action in the courts or whatever tribunal exists in your state for small claims (typically <$10K). With the small claims route, there are some costs involved, which usually must be paid by each party. If the value is above the relevant threshhold, you will be looking at county Court or Supreme Court action, and legal help at your cost. Any court action will be evidence based, and as the plaintiff, it is up to you to prove your case. The state fair trading office or ombudsman should be able to assist with phone advice as to what you need to do to assert your rights.
If the business won’t help you need to put it in writing. Clearly state the issue. Include dates and times where possible. Include what you have done to try to get the vendor to resolve the issue, and the reason that this is not acceptable (e.g. if it falls short of your consumer rights). Write dispassionately, so that a judge (or other independent adjudicator) reading it would find your explanation reasonable, objective and not abusive. State clearly what you want as a settlement outcome (e.g. your money back). Be polite, but assertive.
Unless the business is run by a belligerent person they should want to close it out and avoid spending a lot of time on it.
