Having been quoted £250 per window for mechanism repairs, I contacted Grays Locksmith. Prior to my repair appointment, Grays emailed me, outlining all potential costs. On the day of the visit, as promised, I was phoned in advance. Alex and Jody, who attended, were so efficient and polite, explaining what they were doing at every step. I now have two perfectly working window openings, at a fraction of what I was quoted by others, with replacement parts guaranteed for a year. Highly recommended!