I work for myself and my family, not for a large company. There is no rota of subcontractors and no driver you have never met turning up. The person who quotes your car is the person who cleans it, and that is the entire reason the standard has not drifted since 1998.
The van does the hard part
It carries its own water tank and its own power supply, which sounds like a small thing until you have had a valeter turn up and ask to run a hose through your kitchen window. I can work at an office, outside a flat, in a car park, on a street with nothing available. Nothing borrowed, nothing to arrange, no reason for a job to fall through.
Valeting and detailing are not the same thing
Plenty of people advertise both and only do one. I do both, and I will tell you which one your car actually needs, including the times when the cheaper answer is the right answer. If your paint is sound, you do not need a correction. If it is swirled to bits, no amount of waxing is going to hide it for long.
Methods, not marketing
Two-bucket washing with grit guards. pH-neutral pre-wash before anything touches the paint. Separate tools for wheels. Iron and tar decontamination before any polishing. Paint depth readings before any machine work. These are not selling points, they are just the difference between cleaning a car and slowly wrecking it.
The guarantee is not marketing either
You look over the car before you pay. If something is not right, I put it right. That has been the arrangement since day one and it is why so much of my work is repeat customers and people they have sent.