After what appeared to be a normal takeoff and initial climb, witnesses observed the aircraft level off at about 200 ft AGL and some heard sounds of power cessation. The aircraft was observed to commence a left turn during which the bank increased to an excessive angle. The aircraft pitched nose down and crashed in a gravel parking lot in an industrial area of the city. Investigation revealed the engine-driven fuel pump shaft had failed at the manufactured shear point due to binding of the pump blades against the bore. No foreign material was found in the bore but a small sliver of black rubber was found on the pump relief valve poppet. Engine fuel hoses had been replaced prior to this flight. Boost pump switch found in 'off' position. Previous aircraft owned by pilot had fuel boost pump switch located in different position in cockpit. Pilot/owner at controls not medically certificated. PIC in right seat not current in make/model.