So, you’ve designed a great looking poster. Posters are sold all over Twitter and other social media sites, and now you’ve been lucky enough to land a space in Amazon Marketplace. You’re not the only one selling posters, of course. Some even resemble yours. Great minds think alike, after all. So, how do you know what price to advertise? Prices are constantly changing and being discounted on Amazon. Overpricing on a sensitive item like posters can make you dead in the water. Yet, you need to cover your costs and make a living.