Asked for quotation only but got charged for repai

Handed in broken watch for a quotation on repairs ONLY. Weeks later got an sms saying watch ready for pick-up. Now I have to pay R600 for repairs to have my watch back, after ONLY asking for a quotation. This is unacceptable as I could have gotten it repaired somewhere more affordable. R600 is the price of a new watch and I never gave permission to go ahead with repairs, after explicitly telling them they should inform me of any costs involved BEFEORE going ahead with any repairs!! Isn't that what a quotation is??