Doug,
I have bought Mod. 15's for $150. I still own them and they still shoot great. I once had the chance to buy a DW 357 AND a DW 44 for $300 total, but I did not have $300 (I was a struggling college student at the time) Some of the reasons why used Dan Wesson guns are cheap is because the have had financial problems in the past and the company has gone into and out of business a couple times. One reason the price has started to go up again is that Bob Serva bought the company and started making the same designs with the same great quality, if not even better. Most recently they have just been purchased by the popular Czech company CZ. Anyway, some think the company might not be around and that always reduced resale value. As Unspellable said, the DW design is just so radically different from the norm, that many have a hard time accepting it, even though it is radically better. That should begin to change as many companies, most notably S&W, have begun to incorporate DW features. The new S&W X frames have a barrel and sleeve just like Dan Wesson and Dan Wesson was consulted in the design process for the new Smith. However, S&W made the barrel change a proprietary factory process instaed of making it possible for interhcangeable barrels like Dan Wesson.
All I can say is, if I can get twice the gun for half the price, I am not complaining.
Roll Tide