11
I value my product as a fraction of it's value for the client. My venture sells web apps so it's slightly different, but if a web app would streamline 75K worth of overhead out of an office's budget, I charge 25K for it.
If it's a one time sale you have the option to examine the client and what value it will deliver to them. If it's a publicly sold product, the options are very different.
The basic formula is to sell it for around 30% of what it's worth to clients/end users. If you can deliver better quality than the next company, pricing in step with them is a big mistake because you can make more and take a better market share by promoting the features that justify the cost.