What price should I ask for my poster?

I was given a and the City movie poster signed by all of the cast members from an old boyfriend when the movie first came out. As I'm moving, I don't really have anywhere to store it, and I don't plan on hanging it in my new place. I believe he originally paid a little over $200 CAD for it from a certified autograph retailer. It's in pretty decent shape, but I don't expect much for it. What would be a good asking price?