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Just so, you know the outcome; for the £140-odd, the plumber tried and failed to fix the sink. I had to get him back the next day and was quoted £1600 to sort the blockage and replace all the drainpipes etc. He was there all day and my landlord got it a bit cheaper for doing a self employed job rather than through the company. But if I had been an old lady on my own, I would have paid £149 and been left with a washing machine full of watery clothes and a sink that was unusable.