With houses getting larger every year, it's crazy to assume anything less than a couple years is possible. An average house is 2.6K square feet and is going to take at least a man-year of time to complete. Materials are about 80% of total labor costs.

Those places with super-low housing costs require some combination of:

1. below average wages for construction workers

2. low standard for building materials

3. surplus of materials to drive down costs