Over the past 25 years I built two; about 1600sf and 2400sf. I did almost everything from scratch on the first, but only GC'd the 2nd. The first was tough. Tthe latter was such a frustrating experience that when we wanted a larger home recently, we subsequently opted to buy turnkey new or existing. In our area, there were enough relatively new homes for sale at prices that beat the cost and quality of new construction, so that's what we did although it took almost 3 years of searching to find exactly what we wanted. That type of patience should tell you something.
Frankly, I was fully prepared to pay MORE to avoid a repeat of living with years of self-construction mess, or headaches of GC'ing another new build. On a typical 3000-4000sf 4-bdrm, either is a LOT, LOT, LOT of work and a FULL TIME JOB. Even smart people are surprise by just how much they underestimate the committment necessary. I have come to realize my time is more valuable than any savings I acheived. Of course, local factors come into play, but realize going it alone can quickly turn into a [expensive] nightmare for the inexperienced anywhere.
I opted to go the route on the first because I didn't have much $, was single and could wait for or scrounge good deals on materials. But when I got married, the house was still unfinished and my wife was much less patient living with tools and tarps lying around, drywall dust, etc. and I hired out the finishing touches. It feels like the finish work goes on forever! And, any big cost savings I was shooting for by GC'ing the 2nd evaporated quickly as contractors delayed, failed to show, etc., so they could respond to the builder relationships they were trying to cultivate because they were potential repeat business and I was not. A good GC with a book full of contacts is worth his weight in gold, IMO.
Sooo... unless you are building a very basic, small structure for yourself, have a ton of free time on your hands and are completely confident of your abilities, I wouldn't recommend it. It was an experience I'm glad I did, but have absolutely no desire to do it again.
