Just wondering...

Parts can be very expensive if one wants to build state of the art. For example,  silver output caps made by Duelund will cost $1000 alone. What about high quality transformers, wire, film power supply caps, silver wire, and on and on. A nice chassis can be very expensive with circuit boards and parts isolated from each other and vibrations. Quality IEC, RCA and other jacks can also cost hundreds. 

Now that is only one part of the cost equation.  What about all the time and testing that went into the DAC? I know of designs that have taken two years. Some take more.  What about all those labor hours? What about the education level and expertise of the designer developed over many years? What is that worth?  I have not even mentioned real business costs beyond parts and R&D design. 

So we have all these costs, high costs, poured into a DAC that will garner the interest of a very small group of potential owners. The cost must be spread out over this small group of future owners. Yes, we can see why SOTA gear including DACS can indeed cost $15,000 -$25,000 after mark-ups etc...

Pro Audio Dacs = True to the source as best they can do 
Hifi dacs = Lets make a dac sound different than neutral 
Lets make a fancy case . Charge even more for this !
Skies the limit on what to charge !
Make it sound silky smooth - Charge even more !

I've been diving deeply into desktop audio & headphone listening for the past 1-2 years. In that connection, I've used 2 DACs that impressed me greatly, albeit for very different reasons:

1 - Peachtree Audio DAC iTx: It may be inexpensive (~$300 list), but this humble little box, complete w/remote control, outperformed every other DAC and/or CD player I've heard over the years. w/o delving into technicalities, let's just say that it sounded more natural, less bright/sibilant, and was altogether more listenable than any other device I've used. It also has great input flexibility, being able to rapidly switch via remote control from USB to optical to coax input. I'm fed it via the coax input, which sounds best to me (courtesy of a Musical Fidelity 192/24 V-Link & Oyaide RCA coax cable--the latter highly recommended).

2 - Audio GD NOS-19: It cost ~$1,000. Audio GD is a Chinese high-end company that gets much love in the headphone community. This DAC is one of 2 resistor ladder (R2-D) units they make. You'll have to do some reading on R2-D DACs, if you're not familiar with the term. My version of their R2-D DAC is non-oversampling (thus "NOS" in the model name), and is easily the best digital I've ever heard--relaxed, natural, analogue-like. Again, I use the coax input, which sounds best.

Both DACs are highly recommended.

By the way, I also own one of Audio GD's "all-in-one" products (combination of preamp, headphone amp, and DAC), the NFB-15.32. It's also very competent and good for what it does...

Note that'll I'll soon upgrade my S/PDIF convertor from the MF unit to a much touted new Chinese unit. This will only matter to those who obtain their signal from a computer via USB.

" Pro Audio Dacs = True to the source as best they can do
Hifi dacs = Lets make a dac sound different than neutral"

Then why don't all pro audio dac's cost and sound the same? Sound quality varies just like dacs for home use. 

What method do you use when determining what dac's come closer to the source than others?

I believe that as far as for home audio, this is as fancy as you can ever go with DACs:
http://www.sweetwater.com/store/detail/ZodiacPlus
There is also optional external power supply that makes this toy almost twice as pricey. 
Is there any sense to compare sizes of Antelope Audio and size of company that built $32K DAC?  Because size matter -- bigger better..