Your physical damages of comprehensive and collision should cover the damages of your vehicle up to the actual cash value (ACV) of the vehicle.

If you had hit the deer then the resulting damage would normally go through your comprehensive coverage. However since you swerved and avoided the deer but then hit the guardrail and then continued to crash by rolling over then it will likely be your collision coverage that will be used to cover your vehicle. Your agent will tell you which coverage should be used and the deductible amount that will be due.

If it is determined that your vehicle is a total loss, which if it has extensive damage due to the severity of the accident your described, then your insurance policy would settle with you for the ACV of the car. How ACV is determined varies depending upon an insurance company's guidelines and state laws however typical ways in which an insurance adjuster will calculate actual cash value include: comparing your vehicle to local sales of the same model car in similar condition and with similar mileage, blue book or Nada guide values and/or a computerized evaluation process.

It would appear that you are paying off a loan on the vehicle and want to know if ACV would pay off remainder of your loan balance. If the ACV amount is the same or more than what you owe then it would pay off your vehicle. If instead you are upside on the loan, meaning you owe more than the ACV or worth of the vehicle, then you would owe the balance of the loan over the ACV settlement amount.

If the ACV does not cover the whole loan amount then that is where Loan/Lease GAP insurance applies. If you have elected GAP insurance then it should pay the difference between the ACV settlement payment and the balance due on your car loan.