Important: several of the "next installment" links point to the same one, instead, and you have to hand-edit the link to get to the next one.

Something not mentioned that I found surprising was the very large fraction of construction cost consumed by zinc, for corrosion control, vs copper and steel. I guess that for finance purposes, zinc is considered part of the steel. Maybe availability and price of zinc is stable enough not to need separate attention, unlike copper.