Deductions- car valuation info unavailable

Hi- are you only answering questions about tax refunds? My question is about deductions.

 

I sold a car last year that I used for business. It wants me to input the value of the car at the time I started using it for business (2017). I called Kelley Blue Book, and they told me that they did not have any records on car models earlier than 2009. Mine was a 2008, so they do not have the info. What do I put, or is there anywhere else I could get this info?