Dealing with Licensed Properties

[Coolhand]

I was wondering if anyone here has had any experience with developing independent titles based on any kind of existing licensed property? If so, are there any kind of standard practices that are followed (ie. royalties vs. upfront purchase of the license), and to further that, what would be a standard figure to have to pay for using a license? I know that that question would have largely to do with the property in question (ie. Spiderman would cost a wee little bit more than Wonder Woman), but I just wanted to throw it out there in case anyone has dealt with this before.

The reason why I am asking this is that I have an idea for a game based on a certain not-that-well-known IP that I think could cater well to the community of people who *do* know that IP, as well as being a way to introduce new people to the IP. It's not something that I'll probably act on very soon, but I'd like to create a demo of the game I have in mind before approaching the rights holder to this IP (I do know that there are no currently existing games out that use this IP). And when I do, I want to be prepared to be able to convince them to allow me to develop this title rather than to try and sell it to a bigger fish (other than just the fact that I am probably the only one interested in this IP and think that it can make money if handled properly).

Thanks for any input / advice :)