Ars Repair & Installation

The technician came to repair my Samsung refrigeration. He just stayed for less than 15 minutes and only based on my explanation of what's wrong with my fridge without removed a screw to check. He said a new control board for display panel should be replaced, but the parts is no longer available since my fridge is more than 7 years. I asked him to check with Samsung Parts department and their parts suppliers. He said he will ask ARS to check and call me later. No reply from ARS for the later days.
I checked with Samsung Parts and other parts supply companies, they said that the parts for my fridge model is available. So I called ARS to see whether they found the parts or not. They have not done this until I called and said they will check and call me later. Two days later, they called me and said the parts was available and told me the total cost (labor + parts) will be C$460. I knew from Samsung that the parts cost C$150, so ARS labor charge will be $310. It is so high to my expectation, so I refused to let them to do the repair as they are dishonest from the beginning to find parts for customer.
I don't know how frequent they just send technician to customer and saying that there is no parts or cannot be repaired and charge customer the diagnosis fee $120 without doing anything. Their service makes customers feel very disappointed and not reliable.