The Texas Owner-Builder Crowd
There are two main reasons for building your own custom home. Most owner builders would tell you they decided to go this route because of money and control.
The money you save isn't really "free" money. Since you will be doing the work of a construction superintendent, any money saved was essentially earned in the form of equity. A popular term for this is sweat equity. This amount should be at least 10% of the overall project. For instance, if you would have paid a general contractor $400,000 for your home and his services, building it yourself will save you $40,000. Now, if your a full-time employee and doing this on the side (completely do-able by the way), where else could you find a part-time job for about 9 months that pays that well!
As your own contractor, you have control of many things that were previously out of your hands. For instance, change orders. You want a door moved, or the driveway wider; that is going to cost you more than just the price of the materials and the changes cannot be made on the go. There is a ton of paperwork involved on top of the added cost.
Do you want to be in charge of quality control and choose your own sub-contractors? Build it yourself. You can even select your own suppliers and take all the discounts for your own wallet.
Finally, you have the option of doing some of the work yourself, without asking permission from a builder. It sounds funny, but if you work with a custom builder, and you want to do some of the work yourself, you have to work that out early on, and be pretty specific about it. When you are the owner builder, you don't have to ask permission.