I am sorry, but your question is unclear. How would what come about in mediation? You don't have the money to pay who off for the business? Do you have a business with another person and they are demanding this claimed value? If so, on what basis do they claim this? Written agreement? Oral agreement?
Do you have an agreement that requires mediation? Is that written or oral? As to the best approach, since you provide two unclear sentences, the only sane best approach is to hire a local business attorney to advise you. You need legal advice. Good luck.
This answer is for informational purposes only and is not legal advice regarding your question and does not establish an attorney-client relationship.
Mediation in Florida is a private proceeding which takes place out of court. Nothing used in mediation (with a few unusual exceptions) can be used in court. If you are trying to reach an agreement with somebody, perhaps mediation will work for you.
Other than that, I don't really understand your question.
This is a summary based on incomplete facts. You should not rely on it as legal advise. No attorney-client relationship is intended to be formed.