Terrible workmanship

Terrible attempt at building a garden shed, nails through the roof sealed up with silicone, roof beams already sagging after 2 days, varnish splashed all over my walls. Then when i call the owner Saul he said he was to busy to come view the workmanship his guys are doing. His answer to the roof they put up and nailed holes in the wrong place was that there is no rain so its not a problem. Please do not use this company to even put up a dog house let alone a garden shed.