OK, I think another couple of points being missed here is that catalogue valuations are projected averages. In other words, even electronic valuations on the internet are dated as soon as generated. Also, a piece sitting in stock in somebody's small antique shop may have a low price - much lower than posted valuations, and yet languish there. Not great probability, but possible. The same piece for sale in some remote European non-internet sale may go for quite low. Then a similar piece may come up slabbed at a Heritage sale and go for many multiples. Anyway, those are a couple of ideas. In other words, a dated valuation must serve in a variety of circumstances - that is a difficult task to come up with such.