I'm detailing a car for a cousin and he wants an OTC that will last. I've had very good luck with several layers of Klasse SG and topped off with P21s. As we all know, carnaubas won't ever last as long as we want. Can something like M26 be layered or does it contain cleaners? Are there any OTC waxes that don't truly contain cleaners? He'd like to maintain it himself after I'm finished with it. And he's not really interested in ordering online. Thanks in advance.