The first poster Gary is offering is one of Jeanette Voerman from The Asylum, but he wants you to obtain a copy of one of his original films called "Tap Hotel" before he'll hand it over.
Anytime after this first meeting, stop by your Haven and check your email to learn that Gary is doing a little spring cleaning and has a few posters available to help lend some eye candy to your Haven. This unofficial quest will not begin until after you've met with Gary at the end of the Nosferatu Warrens during the The Epic of the Ankaran Sarcophagus quest. Did we miss any information for this quest? Is there something we didn't discover? Let us know!