To all the questions about including costs, the only blog I've ever come across that was transparent and honest about costs of building a custom home was Mike Davidson in http://ahousebythepark.com/journal/

Granted this was 2010-2012 on a super-desirable WA plot, and inflation has probably 2-3x'ed, but still, it's a very interesting read and a good model for how to disclose costs and still maintain a modicum of humility.