D. lehmanni are the definition of a rare frog in the US hobby, and also hold a title of being extremely hard to care for/breed. I feel lucky enough to have even seen some in person. These are frogs that if available, usually only go to close friends who have lots of experience (aka enough to keep them going). The colombian eggfeeders still have numrous kinks to work out in their care and breeding so I don't know if they could be considered at the same level of most pumilio (except maybe BJs which also have some irregularities we need to figure out).
Having no experience with eggfeeders would be a serious problem. Work through the easier species, like what you have, and then work up to the thumbnails, and pumilio. With experience and reputation in the hobby, eventually you may be able to get your hands on lehmanni as your "dream frog."
The price is set high to reflect their rareness and hopefully deter those that don't have the experience to care for them. $450-$500 each is what I have heard for the few offered publicly.
