I'd love for it to be visible on all book pages if I already own any edition of that book (similiar to the way it always tells me if I've read another edition of the book).
Through time, I've bought a lot of e-books at 0,99 because they were cheap and I've heard good things about them, but it's not easy to keep track of all the e-books I own. Sometimes, I go search for a book, open the book page and I don't realize I already own that book because I'm not seeing the page for the specific edition I own.