Blue book value for big bores

I hate to do it, but I need to thin the herd. And it's a big herd of big bores. I'm really not sure what they are worth. Anyone have an idea of a reliable blue book for these bad boys? To make things worse, I just inherited a few more I need to deal with. I have six I'd like to part with. I'm not sure if I should list them here or on the classifieds I hate to post them on the classifieds before I know what they are worth.
 
That makes sense to me for production guns. Most of these are from yesteryear (I've been told to deliberately misspell them, so I will)

I have two.495 Quickenbush Ser174 and Ser 600

.45 Gaargoyle

.357 Coorsair

9MM Careeer Ultra

.58 Extreeme (this was a special build)

.58 Quickenbush pistol

For a long time, some of those guns went for twice the purchase price. I'm certain that is no longer the case.