I would start by phone consulting and telling them you want the scans to look the same as if they were printed on professional Kodak paper. Commercial paper used by most all consumer labs gives more contrast and saturation.
If that does not work, ask for no correction, i.e. flat right from scanner, and you finish at home. If they add saturation and contrast, it is difficult to remove.
I gave up on color neg because most labs use commercial paper. The answer is a decent digital camera shot in raw. Or if you must use JPEG, turn down contrast and color.
Contrast and saturation is what most people see as quality. If you do not believe me, go to a TV shop and see them all turned up to the max. They look really ugly.