A bit of good news. Despite all the inconvenience and uncertainty you are in pretty good shape on this claim. If you are already working with your own carrier and they are on your side, then do the claim and let them recover your deductible. If they say they are going to go after your deductible they will do so. If your carrier does not believe any part of the incident was your fault your rates will almost certainly not go up. State Farm dug me out of the same situation three times, recovered my deductible, and my rates did not go up. The whole thing was inconvenient, but tolerable.
Based on the facts provided, your best available option is to go through your own carrier for property damage. Thus, you will pay the deductible and your carrier will subrogate against the adverse party's insurance carrier. Your carrier is likely to zealously pursue the subrogation claim in order to recoup your expenses as a policyholder.
I wish you the best of luck.
This advice should not be construed as forming an attorney-client relationship. Please contact a licensed attorney in your jurisdiction for a consultation and evaluation of your potential claim.
I agree with my colleagues, and would clarify that your insurance will pay for your car damage at 100%, minus your deductible, then pursue reimbursement from the at-fault insurer. This addresses your concern that "20% of the damage falls within my deductible limit." Also, I recommend you contact your insurer monthly to find out the status of the subrogation process. It may take many months, but will take longer if you don't stay on them.
DISCLAIMER: This information is for general information purposes only. Nothing stated above should be taken as legal advice for any individual case or situation.
The at fault party owes you the money. If you can prove your case, you can win in court and make the other side pay your costs. Maybe small claims court would work. http://www.kingcounty.gov/courts/DistrictCourt/SmallClaims.aspx
[In accordance with the Avvo community guidelines, this communication does not constitute "legal advice", nor does it form an attorney-client relationship.]
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