As everyone has already stated - it's a simple case of supply and demand. Trying to "pin" a number to it is futile. Even if you made the worst acoustics on the planet (which I doubt is the case) and there was a demand at that particular price point - then you've succeeded!!

Of course if you add artistic integrity, creative satisfaction and the pursuit of your own minimum reference point of quality and craftsmanship that's a different ball game altogether.