Poor after sales experience

I had recently bought a preowned Lexus from Lexus Constantia, I was very pleased with the initial service I received, at the time of purchase. But their after sales service is sub-par to say the least... I had to take it back several times, for silly things that should have been picked up by the dealership before handing the car over to me. i.e. - child-lock broken on one of the doors. - windscreen needed to be replaced. - auto whippers wasn't working after the windscreen was replaced. such an inconvenience... Not what I come to expect from a premium brand.