In most cases, his insurance should pay to fix both vehicles. His 'collision' coverage on his policy will cover the vehicle he was driving up to its actual cash value. This will take the vehicle's depreciation into consideration. Also, he will need to pay for the deductible he chose. If he has 'property damage liability,' this will help protect the vehicle he hit up to the limits purchased on his auto insurance policy. There will be no deductible to be responsible for with his 'property damage liability' coverage. It sounds like you have 'collision' coverage for your vehicle, too. If he does not have 'property damage liability' on his policy, you can get your vehicle fixed through your 'collision' coverage. Your deductible will apply.