For me personally I have a system where clients pay by the hour for high end work, as soon as it switches from a set price to per hour, I consider that high end work. This corresponds with better polishes and waxes / sealants. For me personally, I don't think that high end work has anything to do with the car. I have restored old daily drivers to new and consider that high end work, just on a low end car =) Just a ideas =)