Do NOT sign anything without consulting with an attorney. You could be signing away the right to sue anyone any further on this case, leaving you without adequate compensation.
I do not practice this type of law, so it's not as though I'm trying to hustle your business. It just sounds like you're contemplating signing a release and waiver of rights when you aren't made whole yet. Time to talk to an attorney.
I want to second Mr. Dane's warning. Insurance companies often give the impression that they want to be helpful and just can't do so until the injured party enters into an agreement so that they can make payment, but the truth is that the person negotiating for the insurance company has one job--to save the company money. Pushing the injury victim into a quick settlement without the benefit of counsel is a great way to minimize the pay-out, usually at the expense of the person who was injured and does not understand fully all of the rights and remedies that he is giving up by entering into that agreement.
Most personal injury lawyers offer free initial consultations, so you have nothing to lose by sitting down with someone who practices personal injury law in your area and is familiar with not only the typical resolution for cases like yours in your area, but also the tactics commonly employed by certain insurance companies and their attorneys.
If you don't know a personal injury attorney, you may be able to find one through the link below.
As I am licensed in Florida and Vermont, I cannot offer you specific legal advice as to California state law. However, generally, if you accept the insurance company settlement offer, they will no doubt request that you execute a release, releasing them and their insureds. This release would bar you from bringing any further action against the adverse driver and owner.
They are only obligated to reimburse you for the retail value of your vehicle, regardless of the amount that you may still owe on the car loan. For future reference, you can avoid this type of situation by purchasing what is called "gap" insurance. This type of insurance pays any difference between the value of the totaled car and the amount owed on the loan.
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