They did a great job stretching ridge down the centre of each stair. These were not originally installed right, no tack strips on the sides. So each step needed these in addition to being restretched. Also had buckle forming at an entrance to a bedroom from bonus room. They fixed it and matched the pattern too, looks seamless. A lesser buckle into the master bedroom was also fixed. Master bedroom also had a ridge across the room, so he moved all the furniture with sliders and stretched that out too. In all about 3.5hrs of work and for what was done, very reasonably priced. You can see the before and after of the stairs below (same great level of change on the other repairs too). We are very happy with the results.