The range in price is very large and depends on many things. You used the word "settle". If both parties are amicable and willing to settle then this is the cheapest and best possible option for all involved. On the other hand, if the parties can't help but fight about the issues then this will be more expensive. The more complex the case is and the more the parties want to fight, the more expensive it will be. Almost every attorney you speak to will be unable to quote you even a ballpark figure on overall price because this is impossible to know ahead of time. This is because even if one party is reasonable and "settlement-minded," its impossible to know whether the other party will decide to dispute an issue in the case at some point.
The absolute cheapest price for a divorce is $395, the cost of the initial filing fee. This can only be achieved through Default Judgment, where the Respondent does not file a response (true default), or the default judgment is entered with a stipulated agreement (default with written agreement).
If the parties are amicable and willing to settle, then mediation is a good option. You would both hire and meet with a mediaton attorney who will facilitate settlement and prepare all the necessary documents. This is a much cheaper option than litigation.
If litigation is inevitable, then there is no telling how expensive it can be.
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