Yes. I believe you should have a heads up on a situation such as this for health and safety reasons.
I would think not. Why purify the air of the oil diffuser if the point is to receive specific effects from the oil?
I review the rooms and the level of cleaning and the specified locations from clients and know right away mostly how long the job will take. If the analysis is outside of their requested time slot I discuss with the homeowner so we can be on the same page.
It depends greatly on personal preference. Personally, I like durable yet fashionable rugs that are easy to clean. I do have expensive rugs that are for areas in which there isnt too much traffic.
I am not sure. I haven't used them.
I have my own supplies but dont mind using specific items supplied or requested by home owners.