From the facts as you present them, the signatures of both the husband and wife are necessary. You should absolutely consult with a real estate attorney before proceeding further.
Please consult an attorney. This is not legal advice. Just a response to a generic question. Each situation is different and requires an attorney to analyze the facts, law and application of the facts to the law.
Good advice from the above attorneys. I will add one thing that maybe the listing agent did not properly explain. It may not be the case, but the agent may have been referring to the husband granting the wife or the bank a Power of Attorney for the sale of the property. If that is the case, then the husband does not actually have to provide HIS signature because he has authorized someone else to sign on his behalf. That is the only reason I can think of that the husband would not be required to sign the transfer documents.
Unless the seller can provide you with a title insurance commitment showing that she is the sole owner or can provide a valid PoA, the husband must sign that document. You will definitely want to have a lawyer who specializes in Florida real estate transactions on your side to review all the documents.
Finally, if the property is subject to a homeowners' or condo association, you will want to pay attention to how much is owed in past due assessments, as you may be required to pay all of the outstanding assessments.