The helicopter was substantially damaged when it impacted terrain during takeoff. The pilot stated that the helicopter was to be loaded with one passenger in the left seat and a 167 lb part behind the pilot. The part was loaded onto the helicopter and the pilot was then informed that the passenger would not be riding in the helicopter. Because of a "time deadline," the pilot decided to fly the helicopter from the left seat instead of the right in order to "have a good lateral C.G." During takeoff, the pilot reported that the helicopter started "sinking toward the ground" and that he was "over controlling the cyclic." The helicopter's skids came in contact with tall grass and tipped "very far forward." The pilot tried to level the helicopter with the cyclic, the tail "fell rapidly," and the helicopter subsequently impacted terrain and rolled over on its right side. The pilot stated in his accident report that the accident could have been prevented had he taken the time to get help to move the load to the co-pilot's side. He reported that it would have solved his lateral C.G. problem and he would be flying the helicopter from his normal position.