Market price is the value set by the market, of course, and is different from retail price. The market value of a Noctilux f/0.95 is somewhere between $13,000 and $15,000. Like it or not, that is what buyers are willing to pay for this lens today. The retail value is $10,400, but of course they are pretty difficult to find today. (My Leica dealer tells me he could sell 15 of them today if he could get them.) At some price point, I would be willing to sell my f/0.95 and put myself back on a waiting list to get another sometime in the future. ($15,000 is not it.) As the prices rise in the face of this scarcity, more people are willing sell, keeping a study supply of these lenses in the marketplace.
Of course, an economic crash in China or a sudden increase in the supplies of new lenses to the Leica dealers could change this overnight, but that is also a characteristic of markets.