11. Build For Energy-Efficiency
Don't be put off by the high price tags. Energy-efficient heating systems and "Energy-Star" rated appliances may cost more to install, but can save money (and the environment) over time. The most economical house is the one you can afford to live in for many years to come.
Building Ideas: Build to Save Energy 12. Go Modular
Some of the most interesting and most affordable homes being built today are factory-built,
modular, or prefabricated, homes. Just like the Sears mail order houses from the early 20th century, modular homes come complete with building plans and pre-cut construction materials.
Building Ideas: Katrina Cottages
13. Finish it Yourself
You don't need to be a construction expert to take on some jobs yourself. Perhaps you can take care of finishing details such as painting and landscaping. Also, consider postponing some parts of the project. Leave the basement or garage unfinished and tackle those spaces at a later date.
14. Consult a Pro
When money is tight, it's tempting to skimp on hiring a pro. Keep in mind, however, that architects and professional home designers can help you avoid costly mistakes. Pros also have access to money-saving resources that you might not find on your own. To cut your consultation costs, sketch out your ideas before your first meeting.
Building Ideas: Do You Need an Architect? 
