The costs of mediation are shared equally between you and the other party, unless another arrangement has been agreed or ordered.
The costs can include:
the mediator's fees:
the costs of witnesses and experts (if needed):
the rental of a meeting room (if needed).
Only lawyer's fees, if you hire a lawyer to advise you personally during the mediation because you feel it is necessary, and your personal expenses (travel, meals, etc.), are not shared with the other party.
In addition, court costs may apply if you want to have your agreement endorsed by the court (homologation) to give it the same force and effect as a court judgment.