I string my own rackets. For labour only I ask 10 euro's. Depending on the strings it will be 12.5 euro (bg65) or 15 euro (bg80,ng98,ultimax66) Guess I am kinda cheap in Holland.
In my part of Canada, the average at clubs seems to be as follows (ballpark) BG 65/65Ti - 22/24$ CAD BG80 - $30 NBG95 - $32 NBG98 - $34 BG80P - $38 they appear to order North American string which seems to be the reason for high prices. I order from MBS most of the time and charge less.... mostly just for intermediate players.
most non-pro stringers charge 5gbp for labour, or roughly 10gbp with strings around here. the pros charge around 12gbp for labour, though quality can vary greatly.
I do stringing only for my friends. Charge 120-140 SEK depending on string (BG65-BG80). Racket shop at the badminton hall takes 200-240 SEK ...... Think I will break even two years after invsting in the machine, from now on every stringing is making me money