There's an artist on Fiverr offering to draw graphics. I asked if I bought a picture from them if I would be allowed to use it on my Kindle book. They said that was fine as long as I give them credit. I haven't actually released any Kindle books yet, but I'm working on my first fiction book. First off, is there a place in the Kindle format to give an image credit? Secondly, do most people on Fiverr make requests like this one?