Air conditioning system doesn't cool down the room

93955Sun Rain from Seaside, California owner Bieu Bonney Jr. firm bid a job to install an air conditioning unit at our home. The unit does not cool down the room one degree. Bonney measured room, inspected our furnace and duct system prior to his firm bid. He now says that his firm bid was wrong. When we asked him to remove his unit as agreed, he screamed and threatened us because we didn't agree to paying the extra 30% more over his firm bid to do more work on the system. This threatening has caused my wife to be afraid to have him on our property. He calls us and yells non-stop for 20 minutes, refusing to let us speak. He is not honoring his commitment to his bid and wants us to pay for his poor professional estimate of the A/C system needed.