what is the cost to file to contest conservertorship?

2 of y siblings have filed for conservertorship of my Mom for control of the assets and property. one is an addict and the other has multiple bankruptcies, 2 failed businesses, been foreclosed on a couple of homes, and has Judgement(s) against him. they are not the appropriate choice for conservertorship. my parents were neglected by their children all in Tulare County, and my father died as a result of complications from covid. Its better if the state takes conservertorship.