I ended up happy with the result, BUT..
In the beginning they got confused about the treatment that I chose, and I had to tell them about their mistake. That was ok, no big deal.
I wanted the balayage treatment and they told me -once I had my hair wet- that I had to pay £15 more to have it coloured. I really thought that was include. What is the balayage then? colouring?
When I had to pay, they told that their machine did not work. So I had to withdraw cash from a nearby ATM. Then I paid the price agreed in this website + 15, but without receipt.