Mobile homes are subject to the greatest risk of damage becuase foundation systems for mobile homes often just consists of blocking and strapping to hold the home to the ground.
The other major consideration is the ground your building is on. It is important to know where fault lines are located, but remember that about half of the major destructive earthquakes occur on faults that no one knew about (Kobe - Northridge). It is also important to understand the kind of ground your house is built upon. Soils that are subject to mass failure can result in damage occurring far from an earthquake. In the last major earthquake near San Fransico ground failure occured near the fault line and on land filled in, near San Fransisco Bay, far from the fault line. The land between the two zones was largely uneffected by the earthquake. Consult your local building official for information about local soil conditions.
The Disaster Center The Building for Disaster Page The Earthquake Center