I'm interested in part 4, and would likely pay $5-10 for a digital book that contains it, so long as it were favorably reviewed by other members of this community. (Other guides to this exist, I'm sure, but I'd rather pay $5 than spend the time to track down a good one.) I would probably skip part 1 entirely and skim parts 2 and 3 to confirm my impression that it contains nothing new for me.