There is no way to answer this question without knowing the details of your case and what sorts of damages you are claiming.
Nuisance or nominal value can be different based on the facts of each case and the jurisdiction. Nominal can be as low as $1.00, but typically if an insurer is throwing out nuisance value, it is something which will cost them less than the costs of litigation. To get a better idea, contact an experienced attorney in the area to evaluate the merits of the case.
Nominal value is just that, nominal. Likely less than the actual cost already put into the case by the attorney. Essentially it would mean a zero gain when it's all said and done.
There's no way to say without knowing the facts of the incident and the injuries claimed by plaintiff. If you're the defendant, just let your insurance co. and their lawyer handle it. It seems you're overthinking this.
It is a relative term. It depends upon the facts of the crash, the alleged damages, etc. Sometimes it has to do with costs of defense. Ask your ins co how much it intends to offer. Your ins co is supposed to protect you from a possible judgment over your limits.
Defendant should not play lawyer. Defendant should let his insurance company resolve it, and not concern himself with what insurance company does.
You need to work with your insurance carrier not play lawyer. Probably, there is some risk to you to stubbornly proceed in litigation. Imagine reasoning with a mugger.
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