Marty,
Your absolutely correct on that assumption.
I always remind the folks who like to bring them out of the closet for me to look at, is that it will only be worth what someone is willing to pay. The ES330 I spoke about, I knew was worth something and that it was only worth something to me. And if by chance it was worth more than my sentimental value,
I would have it included on my homeowners.
The other 2 I have mentioned, the bronson belongs to a 70 year old lady who recalls taking lessons at the age of 9. The guitar is in relatively good shape ( the house its in is like a museum). To her its worth $$$, I will assume because of the sentimentality of it. And that I would never take away. The other one, The epiphone I mentioned, I'm not certain of its value..sentimental or otherwise. The gentlemen had learned to play it when he was 9 years old too, but that was all I could get out if its current owner ( his widow). I did find a posting of a guitar (also an epiphone) that looks very similar that was played by Jackson Browne, but his is 1 year newer.
Ah well...if nothing else....a guitar will have value because of the love affair between instrument and owner.

Keep on strumming,
Melissa