Went for regular maintenance, and I showed the age...

Went for regular maintenance, and I showed the agent a piece of plastic dangling from the bottom front of the car and asked him to also have this fixed. He told me the visit will cost around $200, then after 20 min he told me the radiator and rear brakes need to be changed and the cost is $1600. I trusted what they say, and asked him to go ahead. 3 hrs later I was told the car is ready. I looked under the car to find the same dangling piece! The agent, not the mechanic, offered to go under the car and add a clip! I told him I could have done that at home, I need this to be looked at by a professional as I requested before. The manager drove me to the mechanic shop. They raised the car to find out that the entire lower front pad is missing. The mechanic told me someone was changing the oil and forgot to put this back ! I told him I don t go anywhere else to change the oil but here!! The manager placed an order for the missing part. I would not have discovered that without personally going to the shop and look at the undrside of the car. They looked at it on their own and no one brought it to my attention. Also, now that my trust is gone, I asked to see the old radiator. They showed me a group of them telling me that mine is the one on the top. When I asked to see the new installed one, he pointed to something in the engine and said it cannot be seen, so basically one cannot confirm there was a defect in the radiator or that a new one was installed. If there is a major repair with a lot of expenses involved, they should give the owner the choice to go to the shop to see the error results and the actual defect whenever possible. My trust is gone with the wind! I need a site manager to contact me regarding this incident