Rutan: If an employer flies a team of say plumbers to a job in his own plane it's a private flight as it should be. If in order to complete that job they sell one tap washer that they carried with them it's a commercial operation.
Are your sure?
I have flown a LAME out to field job in the 206 as private flight.
He does the job, including "selling" the parts and oil.
I would think that there would have to be commercial gain for the pilot before it became airwork or closed charter.