My advice would be to have your hair cleansed to lift out as much colour as possible, you may need to have highlights put in it to try and get lighter peices through it. you need to start to grow the colour out.
As for cost it depends on looking at the hair to know how long it would take to establish what time is needed to cleanse your hair.
You will also need to put a treatment on your hair after as it will need the moisture put back into it, and you may find you need the ends trimmed sooner than usual as they will feel more porous than usual.
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The Team at Matthewdavid Bespoke Hairdressinghttp://www.matthewdavid.co.uk
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