Regardless of the "value" shown in TCDB or on COMC or Becketts or wherever, I have an image in my mind of what they are worth. Likewise for each of you, although you may use those or others as reference.
When it comes to trading here, make an offer that you think is fair. If the other agrees, great. If not, they'll either counter or decline, and hopefully send a message to communicate a bit and establish something more amicable to both sides.
I will complement the community that I haven't received any outrageously one-sided offers from any of you, yet. (But please don't take that as a challenge.) And hopefully you all agree with my proposals having been "in the right ballpark" at least.