Got hit in my dart

I have worked in the Insurance industry for over 17 years.
I have been to Washington many times to many shops up there its the same as it is everywhere, the insurance company has to pay you for all the damages and needs to put you back to pre loss condition.

First thing not to do is to not argue with your insurance adjuster- this will only make things worse- be polite and point out mistakes nicely. Build rapport with them if possible, you are not driving a honda and they know very little about your car. If you come off to strong up front it makes the process bad for everyone

Is your car currently in a shop?
Did they do a "virtual inspection" to determine 4200- Avoid virtual inspections - you want in person inspection only

I would say 4200 may be dead on in your area as labor rates plays a part. your bumper is shot gas tank shot you more than likely have rear body damage. Cant see any frame damage in the photo you provided.

Don't get hung up on the number, the most important part is WHAT are they repairing and replacing
Take it to a shop that knows, works on old cars- you may have to do your research- but they are out there in the Washington area
Do not take the big chain stores, unless you want it messed up they are all about production speed and cost
If you have parts of your own its ok to use them , but ask to be compensated if you have some that will be used
Speaking of parts- start gathering the sources for the parts- your shop will need the help

Shoot me a pm if you want more information too, I can be help you through the process