I have just come across this post having checked the 'new posts' section for views/replies to a wanted post I put up earlier today, and totally coincidentally, I sold a pair of buckskin ET's a few days ago. I did not advertise them, a guy came to buy a 2000 P6 I was selling, and spied the ET's in my V8 project, and asked if I wanted to sell them. I said yes, make me an offer, so he offered me £200!! No haggling, he offered it, and I took it! I hate the things myself, and was going to put them on ebay at some point anyway. So yes, people will pay whatever they want OR can afford for an item, if they want it bad enough.
I have paid way over what 'some people thought I should pay' for a part I needed badly for another Classic car I have, because I needed it, could afford it, and owning the part was more important to me than its cost. On other occasions though, I have turned down parts because I did not want to pay what the seller wanted, and knew if I waited, another would come along in time, at a cheaper price, because I did not need it as bad as I might have at another point in time.
You take it or leave it, as the buyer it is your call whether or not to spend the money, and as the seller it is your right to ask whatever you want for an item, and you may or may not get it! It really is as simple as that.....