Have actually been my own contractor for 2 houses and helped my father on a few other spec houses before that. Its never a pain free process with subs but knowing what your getting into in advance helps.
Thinking about going with a modular this time (maybe) The place I know actually builds them "square". Once we find the property and pull permits etc., probably 3-4 months and done after well, septic and crawl space (yes a rambler with no steps)