I know the thread you speak of. I really don't think that any figure was actually agreed upon, although 13k was generally considered expensive - but then expensive was considered by a great many to mean much much less than that figure..
The poll that accompanied the thread was something of a landslide as I recall - but those who disagreed with the outcome, in true forum style, refused to attach any significance whatsoever to majority opinion.
"A fortune", however, is a different animal to "expensive". And I agree that, to some, even a million pounds would be considered rather a poor change of fortune...