"take them to court?"

And then they sue you for something unprofessional that you did like not wearing a tux when they met with you.  We all have difficult clients and we all have stories about dealing with jerks like that.  Some of us won't even disclose where they buried the bodies when they reached the breaking point of dealing with these people.  Ok, nobody has ever killed someone over a tax return............ well, at least I don't think they have.  It's just another learning experience for next time you go down this path so that you don't make the same mistakes, like trust someone that shouldn't be trusted.