I did KDP for an author, from Word. It wasn't nothing. I valued my labour at $0 to get experience, There are a LOT of fine-grained issues to resolve, bringing a book to printable state.<p>Binding is it's own special hell: There are huge expectations of barcoding, which plays with your cover artwork, and the positioning of things on the cover is a function of the width of the spine, which is a function of pointsize, margins, wordcount, paper density/weight/thickness. I became very dependent on other peoples templates and calculators to "get this right"<p>Perhaps the oddest part of this, is the join over paper and ePublishing: they are very unequal in terms of DPI expectations, for both font and artwork. I think the golden rule here is "preserve your pixels as long as you can" but there is also "think about metadata, in images and in fonts and text" because producing print ready PDF and ePub formats, the meta is what the printery/bindery is going to work with. EPSF and other stuff comes to the fore very quickly.<p>Page numbering is another bugbear: some places demand you DONT number pre and post, some expect it to reset, some expect one to be roman numerals, the rest in decimals. some want it spine, some want it edge, some want it centered. Get too close to the margins, now the printer hates you...