I've tutored for over 12 years as an unqualified teacher and as a qualified teacher and parents really don't know the difference. They think unqualified means no qualifications at all when all it means is not having QTS. Many tutors have Masters and Doctorates. As long as the tutor has a degree or is working towards a degree, most parents will think it's okay. There are some 'posh' agencies catering for the exclusive areas in London and their tutors are charging £35+ an hour and many aren't qualified, some are just A level students. There is one agency that used to be called Oxbridge tutors and boasted all its tutors were Oxbridge students or graduates.