I'm at a lower figure than those above. I see rust on that brake caliper. Value of components are all about condition, people don't want parts with rust. And if you treat the rust (time), there will still be pitting. Undesirable. Cheap, crap steel seat post.
Personally I don't play the make an offer game. Seller needs a price. In the end, I would pass, as anymore, I just put my time into better projects. Time is precious.