Originally Posted by
Often1
Write a short letter to the caller simply confirming your conversation and her statement that she had determined that you have no liability for the damage, if any, which ocurred after you returned the vehicle. Don't embellish and don't write anything which she didn't say. End the letter saying, "I consider this matter closed. If my understanding is for any reason not accurate, kindly contact me immediately." Send the letter Certified with return receipt and staple the receipt to your copy when it comes back.
Personally, I'd say "within 3 days of receiving this letter" or something with a definitive time frame. One's judgement of "immediate" might differ and when they come back in 3 months against you, they can claim they thought that was "immediate".