The pilot reported that, his mechanic had just completed an annual inspection on the airplane, and he was flying it home. While en route at 1,000 ft above ground level, the engine experienced a total loss of power. During the forced landing to a road, the airplane stalled about 40 ft above ground level and impacted the ground hard, which resulted in substantial damage to the upper fuselage. After the accident, the pilot learned that the mechanic had moved the fuel selector from the BOTH position to the LEFT position. The pilot further reported that he did not check the fuel selector position before takeoff. A postaccident examination of the airplane by a Federal Aviation Administration inspector revealed that the fuel selector was in the LEFT tank position. The left fuel tank was nearly empty of fuel, and the right fuel tank was full. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation and attributed the power loss to fuel starvation.