You posted this quesiton in the Real Estate and Real Property section, which means that it is likely you won't get a lot of responses. I would suggest that you re-port this, probably in the civil litigation section, to get some additional responses.
From the facts you posted, it's not real clear what he is threatening you with. I know he is threatening that you should return his money, but is it because you failed to disclose that the car would not pass smog? Why won't it pass smog after it has been restored? Unfortunately, to answer you question, an attorney will likely need a lot more information. Based on what you did post, however, it sounds as if he is threatening you for failure to disclose the defects in the vehicle. That failure to disclose is probably entirely irrelevant if he bought it with the intention of completely restoring the vehicle, unless there is some incurable defect which will prevent him from smogging and registering the car. An example might be a car that was salvaged (totalled by an isurance company) and cannot be brought back into the required safety standards. It doesn't sound like that is the case, but it is hard to speculate without all of the required information. Another question is why you had to get a restaining order. It sounds as if that is what is driving this latest attack. I would be prepared that when and/or if he sues you, you want to put together a defense that includes the fact that it was purchased for restoration, that he was fully aware of the condition of the vehicle, and that the only reason this is even happening is out of retaliation for the restraining order. Good luck - the buyer sounds like a real winner.
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