My question is should I get an attorney to try covering the amount and possible retroactive coverage? What kind?

You need to talk with a local attorney that handles insurance matters, primarily errors and omissions litigation because you are facing this...

I agree with counsel. Once they make a property damage settlement offer, they will only give you an additional 1-2 days to turn in the rental car....

Who would be responsible?

Complicated question, but you could both be liable so make sure she does not drive it without insurance. Good luck.

Sure, why not! Since there was technically no car to insure, I woudl ask f r a refund.

Will I be response to pay back the insurance company after accepting the settlement , if they some day discover they over paid?

How did they miscalculate? Are they paying back your health insurance? Look at it this way, if you miscalculated your medical expenses do you...

If I accept a car ins settlement 4 personal prop damage does that mean I can't take them to small claims if I feel it was unfair

Correct. AAA will offer you a final settlement, and if you accept it you cannot go back and sue for more $$.

What does filing an answer mean?? I do not want to fight in court.

An answer is a formal legal document that responds to the allegations set forth in the complaint. If you have auto insurance you need to call them...

How to collect your full settlement?

I would still try and talk with a local personal injury attorney and have them review the agreement you signed. Good luck.

What legal process is appropriate to receive the requested information?

Since you stated that you have an attorney, you should be asking him or her these questions. Don't go behind your attorneys back, just ask.

I would notify your insurance company ASAP and give then the eyewitness contact info. Let the insurance companies work it out. Good luck.