my daughter's keyboard on a macbook was keying strange
characters due to an inappropriate usage of cleaning liquid. Apple quotation for the repair was 250€. The price for a new keyboard on ebay was 60€.
Using the Guide provided by Ifixit I could repair myself using especially the heavy duty spudger. It took me about an hour because I am especially cautious and slow.
One should always consider do it yourself. especially the Ifixit guides are very good.
Metal Spudger Set
Heavy-Duty Suction Cups (Pair)