Hi Dkcooper
If you go here
Pentax Lenses by Sigma, Tamron, Zeiss, and more - Reviews and Specification Database - Pentax Lens Review Database you can search for various items and you'll get some idea of price. Alternatively, use ebay as a guide. If you become a member and site supporter, you can sell using our Marketplace. See
READ FIRST: How to list items - marketplace rules - condition key - feedback guide - PentaxForums.com for more information.
You are much more likely to make a decent return if you list each individual item with it's own price and sell individually. A bulk lot sale will almost always result in a lower price for you.
Lastly, please do not negotiate a sale on these forums outside the Marketplace as that is against the rules.
Kind regards,
Mark