No accountability for poor workmanship.

My car went in for a major service and to check an intermittent noise in the suspension. The owner (Mike) told me that they had done a full inspection and the noise was due to shock mounts, which I authorized them to change. Following the service, multiple issue transpired - everything from an oil leak to a rattle in the interior and noises in the suspension when driving. Since the service, my car has gone back in on multiple occasions and even spent an overnight visit at the workshop. Issues remain unresolved. Owner (Mike) started ignoring my calls until I got Bosch Car SA involved (who offer no real assistance). During the last visit, they mentioned that the engine mountings were the issue, leading me to believe that they did not do any inspection. Issues remain unresolved and owner does not want to take accountability for the poor workmanship.