The NCCA course is the one to go for, very good course content, the prop with manufacters coures as i see them, is that they steer you towards there chems and machines,not much wrong with that,but you need to know more about what is out there,the NCCA course will teach you how to clean,then look around at the various machines and types of chemicals.
But training is the most important part to get under your belt first, dont skimp on training costs, you wouldnt expect to be a doctor by doing a cheap course,would you?
Once you have done all this,then with the right marketing, you can expect to earn £60 per hour as a professional.
Dave