I am having an attack of OCD.
I published my first book with double spaced text and sized 5x8 inches.
My two subsequent books are 6x9 and 1.5 spaced.
Any time I contemplate setting up a stall at, eg, our village fair, or doing a promotional talk, I cringe at the disparity in sizes. So I'm thinking of bringing that first book into line.
How difficult / easy is it to rehash a book on Amazon?