The airplane was substantially damaged during a hard landing at at approximately 1740 Pacific time. The Commercial pilot and his pilot certificated passenger were not injured. Visual conditions prevailed for the sales-demonstration flight. The pilot later reported that the passenger flew most of the flight to get used to the flight characteristics of the airplane. On their final landing, the passenger got the airplane into a high rate of descent on final. The pilot took control of the airplane, added power for a go-around, but impacted the runway hard, bouncing back into the air and continued the go-around. Once aloft, a witness on the ground reported by radio that the left main landing gear was damaged. During the landing sequence, the airplane veered off the left side of the runway, and subsequently folded the right main landing gear under the airplane.