If you want market value for your herps then don't put OBO on your ad or 40% of the asking price might be your best offer. It's that simple. It just doesn't make sense that some one writes "taking offers" in their ad then gets offended by the offer.
If you want a certain price then state that price or the minimum you will accept and spare yourself. People posting ads looking for animals at a low price are suprisingly almost always answered as their is usually someone looking to get rid of an animal at almost any price. If I want an emerald tree boa for 200 bucks and you don't want to sell it for that price then don't. Nothing wrong with me trying.
"Only through education do we teach the ignorant that which we love is not evil but wonderous"....