Lots of good info in here. I'll add what I can. I'm a Residential GC, have been for 16 years. I stay mostly on the remodel side, but do some new work on occasion. Here is my .02.
Is there money to be saved? Yes, for sure.
Is it easy money? No way, you will earn every dime you "save". You need to think of it as paying yourself, sometimes it will feel like less than minimum wage by the time you hold the (insert random tradesman here) hand and put up with broken trucks, dead uncles, semi creative random excuses and just plain not answering the phone.
As a contractor I have connections for every trade, but because I may not use them on a real regular basis, I don't get the same service as someone who may need a mason every month. That means I have to be the squeaky wheel to get things done sometimes.
The other thing to consider as a DIY'er is once you find a quality sub, they are typically the ones with a full schedule and many repeat clients making it hard to get on the list.
If I were in your shoes, knowing what I know, the ONLY way I would consider this is if I was going to be on site and physically working everyday. I am pretty picky about quality of work and lots of subs don't suit my standards. There are too many things that can be missed by a "truck ass" contractor if they aren't on top of the project. It is very rewarding to build your own house, but it is also making a big gamble that you may have a hard time fixing later on down the road........
