I never needed braces. Just had a 'perfect' set of teeth, apparently. So mine also cost €0, which is probably less than £0, still more than $0, but certainly less than seven grand! :) I never liked the idea of braces anyways. Do you need to wear a retainer forever after you get the braces off so your teeth don't fall back into their original position? Or at least revert to a more unsavory position?
My sister lost her retainer in Paris one time and never went about getting another one for some reason. I think he teeth stayed in the same position. This was about a year ago.
I also had braces, and I am supposed to wear a retainer once a month for the rest of my life. However, I usually wear it every night b/c when I don't wear it for a week or so, it's very painful the next time I wear it.. and my gums usually bleed