We all know what a picture is worth. But what is an "idea' worth? An agent once said to me, "Ideas are cheap." The context was "Someone gave me an idea. Therefore, they deserve a co-author credit." (And a percentage of whatever is earned.)
The agent felt that ideas are everywhere. They have no value unless you have the talent to execute them well. I don't agree. It's hard to quantify, I think they are worth a lot. If one person comes up with a fully developed idea for a PB and another did all the writing, I might view it as equal contributions.
Recently, I gave a couple of ideas away. (Not fully formed ideas.. really more like titles.) I handed them over to friends who I thought might be a better fit for them than I was. Will I end up have giver's remorse? Maybe... if the stories sell :)
What's an idea worth to you?