[68Hawk]

I don't think there's a major problem asking for offers to determine value of the Jackie.
There's a huuuuge difference between what people 'think' is it's value, based on things as varied as what THEY would feel comfortable paying theoretically if they had the money, to what they last saw one sell at (could be 6 months previous), to even personal discrimination based on the issue itself or it's aesthetics.

Getting hard offers from buyers willing to commit their funds to a real purchase is a series of true numbers you can work from realistically and refer to.

Of course, with every offer the OP should have been contacting the interested party to let them know why he had created the BST thread, to thank them for their interest and to ask if they would not bomb the exercise for a pre-determined time so he could gather enough evidence.
No idea if the OP did this though.

He should have then started a fresh thread to discuss why he made the Sale thread and to encourage discussion of his situation.
Being called to do so by others sure makes him seem less hobby pure and creates the idea he might have actually been willing to let go of his problem to someone else for the right number.