Mike, simply put, the knife is worth what you can get someone to pay you for it. Someone may come along and pay you the price you were asking in the craigslist post, but I have grave doubts you will get anywhere near that from someone familiar with the custom knife market.
I know of few knifemakers who can command in excess of $30 per hour for their time, as you are asking, and they are well known and nearly always long-experienced. It is much more common, as Ren told you, for new makers to get little more than the cost of materials for their knives as they attempt to gain a foothold in a competitive environment. It is not at all uncommon to find that experienced makers with a decent presence to get perhaps $10/hour; it is also frequent to hear "newbie wages" in the $4 range.
One point I will make to you about your listing..... You state that 15n20 is a low carbon steel. 15N20 has 0.75% carbon, putting it firmly in the high carbon steels. Anyone who reads your listing who knows custom knives will realize you do not, and will then think you are a novice. That will diminish their interest quickly, I assure you.
I'm not trying to be harsh with assessment, but only directly honest. These are my opinions, though, and others mileage may vary. I hope you are not offended by my directness. I personally think the blunt truth is far more valuable than pleasant deception.