I have a Johnny Cash autographed Guitar I won in a music contest sponsered by Sony Records. I entered the contest while Christmas shopping at a local record store in Louisville Ky back in the late 90's. (earXtacy records) Recieved a letter advising me of winning and soon after the Guitar came from UPS. I have stored it away all these years in the closet. I will post pictures soon. I have a couple questions.
1. Is it expensive to get an autographe authenticated?
2. How much Would authintication increase the value, if any?
3. How can I find out a rough idea of the guitar's value?