Generally, insurance companies will pay the lesser of the following:
The amount necessary to repair the vehicle or
The actual cash value (ACV) of the vehicle.
Read your policy to determine what exactly is covered. Be mindful of any exclusions and limitations to your policy. For example, there is usually no or limited coverage for enhanced aftermarket stereo equipment, telephones, or tires and wheels unless it is original equipment installed by the automobile manufacturer (OEM).  Additional coverage is usually available for such installed equipment at an additional charge.