Anyone here have any experience approaching IP/Copyright holders for consumer products? Looking for advice

Hello and thanks for reading. Please ask any questions if you need more info.I have a start-up business that produces a range of premium posters.I'm looking to approach a range of content creators to propose an agreement to use their copyrighted content.Does anyone have any experience or advice they can offer to help me approach potential partners in a professional manner?What would they expect? What are the most effective methods?Any help is appreciated via /r/business http://ift.tt/2wlrOEL