1.让你先生给你写个Power of Attorny 代替他签字卖车。

2. 强硬的告诉他， the car was sold in as is condition, if he is not happy, meet in court then.

别理他就行了，如果他强硬恐吓你的话就报警，这种人就这样儿，喜欢欺软怕硬的。