Fees charged by the Court for filing or court events are different to party-party costs.
You are required to pay the filing fee when filing your migration application with the Court. In some circumstances, you may be exempt from paying court fees or a reduced fee may apply. There are different requirements for general exemptions or financial hardship.
If you are in immigration detention you will be eligible for a general fee exemption and should complete and file an Application for exemption from paying Court fees - general (general federal law).
If your matter progresses to a court hearing there are also 'setting down' and 'daily hearing' fees.
For more information see Migration law fees.