I just bought one for $625 at a local camera shop here in Denver, Colorado. I think it was a very fair deal. The glass is exceptionally clean, though there are a few specks of dust inside. There is also a small ding on the focusing ring, but it really doesn't bother me and has no effect on the performance.
I've seen the ver.IV lenses on Ebay for over $1000, which seems way too expensive to me, so I agree with Rafael in suggesting around $600-700 range.
Good luck on your lens purchase.