This is for the TBM 900 and 930. There is no 950. It's a six place aircraft, not an airliner, not a 737. Costs around $4 million not 8. The lavatory weighs 90 pounds and replaces the two rear seats. A quick, 30 minute configuration change. The plane can stay in the air for 7 plus hours at long range cruise so having a lav while flying 4 people is pretty convenient actually.
