There is a difference between custom home builders and production home builders. You will want to select the one that offers you the flexibility that you need. Take some time to talk to both types of home builders to determine what they can provide and what they may not be able to provide to you.
A good way to save money on building a home is to build on land that you own. You can purchase land just about in any location, but you will want to commit to trying to do this first because if you end up purchasing the land from a home builder, it will cost you much more. Find a real estate agent to help you to find land that is perfect for you to build on.
Many home builders will provide you with an inspection about one year (sometimes longer) after the home has been built. Anything that may be structurally wrong with the home at that time can be repaired by them. Cracks, painting problems, flooring issues and more may be covered. Find out if your home builder provides this service and the details of it.