I have a question. I've written a short story, of about 13k words. I have a tetralogy planned out for it. I'm in the process of writing the second story. I'll self publish the eBooks individually, but what about the physical book? Should I just bind all 4 together?
I believe that 13k is more like a novelette than a short story, but I might be wrong. I have seen books with four novellas (novellas are slightly longer) in traditional publishing. I think it has to do with total book length. Even if they were unrelated, perhaps 13k is too short to publish them separately, so I would imagine bounding together is a good idea. Since you are self-publishing it doesn't matter how long it is, and I personally have been longing for shorter books, so I imagine others do as well. But I only speaking based on personal search for books, I don't have publishing knowledge. Even so, I thought I would share my personal opinion at least to help you think about what to do.