Thanks, I finally solve it. They are also polite now.

车修好了. "COURTESY", 所有的刮痕都不见了.

业主还是不想把名声搞坏. 他们的态度今天非常好.
把我的车还里里外外地吸洗了一遍.

我没找什么侦探.我只是平静地提到我正在和一个侦探朋友DAVID在谈这见事.
DAVID先让我估计损失.我有一张侦探的名片. I want to help you find out
the potential enemy in your company who hate you and did such ugly things. He was stimulated
and admited that he was in fact one of the owners and thanked for the suggestion of emplying a detective
to do the investigation. He had the ability to handle it himself.