You need an additional qualification to be able to assess and diagnose dyslexia and I would say £540 is pretty standard for a private assessment. I am in the same position – no local authority assessment for dyslexia. Parents have to go privately or school has to pay for a private assessor (so far my school has never done this. parents have had to sort it out themselves, lack of school budget as always). Shouldn’t be that way but unfortunately is at present. I screen in school using the Dyslexia Portfolio which can give indications but not a diagnosis (and I find it can flag as no signs of dyslexia for children who I feel from school observations / assessments and the pattern of results do seem to be showing some specific difficulties – and in some cases these children have then gone on to get a diagnosis so just a word of caution when looking at the dyslexia index suggestion of that screener). I find that we can pick up through in school observations / assessment / screener most of what is later picked up on in a full dyslexia assessment (I also do a general ability assessment CAT4 that checks verbal, non verbal, quantitative and spatial abilities) and so can have reasonable support in place for a child – most of the recommendations in dyslexia assessment reports I find we are already doing by the time that report comes my way. So I try to reassure parents about that while also at the same time being more than happy if they would like to get a private assessment as that level of information is so valuable but hard to get with decreasing LA assessment and EP services (nothing that is free any more in my LA).