The pilot had just finished fueling the airplane and was trying to start the engine. After several failed attempts to start the engine with the electric starter, the pilot decided to “hand prop” the engine. The pilot subsequently placed standard, low-profile general aviation wheel chocks under the wheels, but did not tie down or otherwise secure the airplane. Additionally, the pilot did not secure anyone to assist him and there was no qualified pilot seated in the airplane during his attempt to start the engine. As soon as the engine started, and the airplane’s wheels rolled over the chocks, and the airplane taxied into a closed hangar door, resulting in substantial damage to the fuselage and both wings, and damaging the hangar doors. Following the accident, the pilot stated that he had not previously received any formal training for hand propping an airplane, but that a mechanic had shown him how to do it. He was not aware of recommended precautions like having a qualified and trained pilot at the controls or tying the airplane down.