The court has the authority to order mediation in a child custody dispute. Mediation is not dependent upon income. Normally each party pays for 1/2 of the cost of the mediation. You could be held in contempt of court for not participating in court ordered mediation. Best advise is to tell the judge that you cannot afford to pay the mediator now and let the judge know when you would be able to pay the mediator. You could also simply agree on custody with the other side.