Builders receive discounts on labor and materials that the one-time owner-builder will never be able to negotiate. Those of us who are any good at this tend to make fewer mistakes and we have a lot of experience that can save money on the job too.

Not only that but we have software and other systems that can make a very complex process much more manageable and predictable. Finally we have a lot of experience dealing with zoning boards, architectural review committees, building officials, etc...

Does every homeowner experience this type of nightmare? No! Some folks actually do a pretty good job. But ask one if he or she would ever do it again. The vast majority would answer, "No,”The best suggestion I can offer is to do some serious research so you know as much as possible before you build.  Visit your local library and do some serious reading about the home building process.  Visit the homes of other people who have built their own homes.  Walk through model homes and neighborhoods similar to what you are looking to build and talk to as many people as possible before you make a decision.  Some books suggest that you can save in the neighborhood of 25% by acting as your own general contractor.  However, since the average professional builder probably realizes an actual profit on a new home in the 5 - 10% range (if they don't make many mistakes), you will need to keep in mind that there are other factors involved.  How much is your time really worth, and how much will the mistakes you make end up costing you?

Courtesy of: www.ICFhome.ca

http://www.ontario-home-builder.com/Home-Building.html