Making a quick buck or innocent mistake?

On 6 November 2015 I took my car to Towbars Cape because the Immobiliser/Alarm was not working properly. The technician told me that he will check the system for a certain amount of money and if the system was faulty he can replace it with a new one and then I will not have to pay this fee. After a short while he came back and told me that the unit was \blown"and it has to be replaced. I told him to go ahead and replace the unit.<br> <br> After a couple of days I experienced exactly the same problems which I had with the old system. I took it back and the technician said it was the \""bonnet switch\"" which was at fault. More or less a week later I had the same problem and took it back again. This time the technician said it was the right rear door switch which was the problem. I had both rear door switches replaced and now the problem seems to have been rectified.<br> <br> My question now is:- WAS THE ORIGINAL UNIT REALLY BLOWN OR WAS IT THE FAULTY REAR DOOR SWITCHES WHICH CAUSED THE PROBLEM IN THE FIRST TIME? WAS I TAKEN FOR A RIDE AND DID TOWBARS CAPE MADE A QUICK BUCK OUT OF ME?<br> <br> I will NEVER recommend this establishment to anybody"