If negotiation doesn’t bring any results, you can try to resolve the matter either through arbitration or litigation. But before doing that, it may be worth asking a lawyer if he or she can help get a more favorable settlement informally.
Arbitration, which is less of a hassle and less expensive than going to court, will usually result in a decision favorable to the insurance company. Insurance companies are practiced at arbitration, and arbitrators have to deal with them all the time. Some arbitrators don’t want to get the companies upset. Having an attorney at arbitration will increase your odds. However, the best bet, if you’re going to try arbitration, is to see if nonbinding arbitration is an option. That way, you can still take the matter to court if you are not satisfied.
Going to court is rarely a cost-effective option. Unless the matter (a car) was extremely valuable, and the insurance company’s offer is a tiny fraction of what you believe the vehicle was worth, you may spend more in attorney fees and costs than the amount you might recover.