Generally speaking "discovery" is the process of obtaining financial and other information so that you can prepare for trial or make a reasonable settlement. You will be able to get almost all of your spouse's documents and information either directly from them, or from third parties or employers etc. So why do lawyers charge so much? Let's take a "simple" example. It does not matter whether the example concerns alimony, child support or anything else. The point is to illustrate why it can take a lot of a lawyer's time to properly deal with just one aspect of the client's matter. Lawyer Jones represents the wife.
She calls one day and says that her husband has decided to fight for custody of the parties child. ("custody" is a term no longer used in Florida, the predominant issue is timesharing regarding the parties' minor children) She is extremely upset and the lawyers spends 25 minutes on the phone with her. An appointment is scheduled. During a 1 1/2 hour conference the wife explains why it is in the child's best interest to live with her. She explains that the husband is making accusations about her fitness to care for the child.
The wife gives the lawyer the names of four witnesses who can either attest to the wife's good child rearing abilities, or respond to the allegations that the husband will make. She is given the name of a psychologist to see for an evaluation of her parenting abilities and mental state. At a minimum, the attorney will need to interview each witness by phone or in person, attend their deposition by opposing counsel, review costly transcripts of the witnesses' deposition testimony prior to trial, and prepare the witness to testify in Court. The lawyer will also have to take the deposition of the husband and his witnesses regarding the accusations and his suitability and the wife's non-suitability to care for the child.
The lawyer spends considerable time preparing for trial and then goes into Court for what could be several days of trial testimony, including complicated testimony from psychologists for both sides. Once the Judge finally rules, the lawyer will either draw up a detailed Order as instructed by the Judge, or at least review the Order prepared by the other attorney before it goes to the Judge for signing. Other matters may include legal research where the lawyer attempts to determine what the Florida Appeals Courts have said about the particular issues involved.
While the above example does not occur in the typical divorce, there are several lessons to be learned. First, you have to be realistic in what type of battle you can afford to fight, and second, you need a diligent competent attorney. Matters like these require lots of hard work, and every issue that you can't settle means more and more steps which the lawyer must take.
As discussed above, any individual who has information relevant to the case can have their deposition taken. That is, either attorney may subpoena the person to testify in the presence of a court reporter under oath, and answer that attorney's questions. As a result of the deposition the attorney will know in advance basically what the trial testimony is going to be and they can plan accordingly. (Also, they can bring up the witness's deposition testimony if there is different testimony at trial, i.e. make the witness look bad by "impeaching" them with the deposition testimony).
A witness may also be required to bring documents to a deposition and make them available for copying. Thus, lawyers can determine what they need to about a party's finances by taking depositions and obtaining records from the party or from other individuals. Additionally, each party is required to file under oath a financial affidavit. (except in "Simplified Dissolutions") The affidavit lists such things as income, expenses, assets and liabilities.