Mr Roofline in Paisley

Absolute disgrace of a company. Never fitted my mums guttering properly and then when she phoned to get it sorted the owner Roddy told her that the 10 year guarantee was void - she then tried to phone back and the number was unobtainable. I then found this number and phoned: asked if this was Mr Roofline and he said YES!
Then when I went on to explain who I was he said the company 'Mr Roofline' doesn't exist, even though he said it did at the start of the conversation (obviously thinking I'm a new customer). Then he said that no one guarantees work for 10 years and it would only have been 12 months - even though the paperwork says 10 years. He also said that another company deals with the guarantee even though he never issued any paper work on this to my mum. The guys a con man - don't go near. We have spoken to consumer advice and are taking this further.