Maybe I could see the lower end of that. Certainly you need a designer that is top notch - but that should be 2-3K, right? And the person that implements it, you will want to have someone who has solid wordpress skills on staff. Yes, they would need to be paid for their time, but again, that should be 1-2K, right? What am I missing that would bring it to the 20K mark?
$1000-2000 is enough for a basic website implementation by a professional. So like a standard ICO site. I've developed things like ICO sites before, it really depends on the amount of pages & features required though.
If special features are required (such as a point system, sharing validation, bounty systems, etc), then it will start to add up.