Service based but somewhat related. I've recently decided in my consulting efforts; if the customer doesn't try to negotiate the price I'm way too cheap. Supported anecdotally by two interactions with the same customer - a colleague of mine from another company went in at a price for some work that I considered way too low. The response from the customer was "when can you start?" I recently quoted what I considered to be a perfectly reasonable rate for some work and that was the start of the negotiation. We had a good exchange of analogies to support our differing positions!