Adjusters know that time is often on their side and will try to wait you out. If you have the time and inclination, do your research as already suggested and present that to them. It matters. Also, in many states, small claims is cheap and easy for the individual to file. But in many states, corporations must be represented by council. That is often more expensive for an insurance company than settling to your satisfaction. You don't necessarily have to go to court, and maybe not even file. Just have your facts in order, present them professionally, and let them know you are not going to settle for less than your research says you are entitled to.

They know the value of your car, and if you are on solid ground with your estimate and convince them of your intent to see the process thru, you'll get better than their initial offering.