If you are concerned about the time it might take to mediate, your best course is to come PREPARED! Bringing organized documentation pertaining to all of the issues to be mediated will streamline the process and keep your time and costs down.
Mediation is meant to be approached in good faith. One party hiding assets, money, debt, etc could very well cause a breakdown of trust that could end negotiation on a dime.
Today I mediated for 7 1/2 hours without a break. I was the one mediating, so i can only assume that it must have felt several times longer for the parties involved as it was their lives that were being affected. It would have been tragic to end mediation because the parties were exhausted by the process and not because they couldn't come to agreeable terms.
If you are preparing to mediate a divorce, come prepared to discuss EVERYTHING and plan to spend the better part of the day FOCUSED on mediation. Deadlines or events planned on the same day may distracting and put undue pressure on the process.
Write something about yourself. No need to be fancy, just an overview.