If the other driver was at fault, then his insurance company should pay for the value of your car (note that this is not the same as paying the amount of the loan). If you are having difficulty with the other driver's insurer, then your own insurance company will pay for the value of your car under your collision coverage. Then your company will go after the other driver's insurance company (through inter company arbitration) and recover what they gave you plus your deductible (which they will then return to you.)
If the amount of your outstanding car loan was more than the value of your car, then you will have a problem, because the obligation is to pay for the value of the car, not the amount of your loan. Once the insurance company has given you the value of the car, then it will not be liable for any additional storage charges after that point and you are only hurting yourself by allowing the car to remain in storage and incur additional charges.
If you and your mother were both injured (I assume you have been getting medical attention), then you should talk to an attorney about a personal injury claim, especially if you had full tort insurance. If, on the other hand, you had elected limited tort insurance coverage, then you waived your right to sue for your injuries unless you sustained a "serious injury" (an injury causing a "serious impairment of bodily function") in this crash. Either way, you should consult with an experienced personal injury attorney to obtain advice as to your rights. Look for an attorney who is a member of the Pennsylvania Association for Justice -- that is the organization that attorneys are a part of if they regularly represent injured victims of accidents like this. Be sure to take a copy of your own insurance policy with you when you talk to an attorney. If your mother owns a car, she should take a copy of her policy with you as well, since the tort selection (limited tort or full tort) will determine whether or not she has a right to sue for her pain and suffering. Only an experienced attorney can give you full and complete advice on your rights and most PaAJ members will not charge you any fee to talk to you about this crash.
This is one of the more difficult issues in motor vehicle accident law; when a car is damaged and the market value of the car is less than the amount outstanding on bank financing. It is true that a negligent driver is not responsible to pay more than the market value of a vehicle.
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