My son had an accident a few days ago, someone rear-ended him leaving a petrol station. He has been very decent and admitted complete liability and was very concerned the occupants were ok. He is happy to pay for repairs without using insurers, though would go through them if necessary. How should I proceed with this and how can I be sure he will pay for repairs if I get them done. My concern is that the cost of repairs may be more than the cars value and to go through the insurers they would only pay out the minimum.