You're asking a legal question which can't adequatly be answered here. I'm not a lawyer. Seek competent counsel.
Rule of Thumb: Remember. You're allowed to do more than you think you're allowed to do.
Just as cops often often arrest people for "hate speech" where it's not illegal, we often think our actions will be illegal when it's not.
The Supreme Court consistently defends free speech. Why? So the media can continue spewing white-bashing hate speech forever. The liberals lit the Milo event on fire so we'd defend the same free speech the media's been using to crush us. So it's legal, even though the only people who act like its legal are the enemy.
Obviously, I can't tell a black man he can't buy my house because he's black. That would be racial discrimination. But I might have him complete an IQ test or see if applicants can delay gratification or solve task-related puzzles before hiring him. "And now, applicants, I'd like you to invent a wheel. Then design a two-story building."
But who says I have to advertise my house where he's ever going to see it?
As for private clubs and religious organizations, I've noticed the states regulate it with religious freedom in mind. If I were you, I'd see the Civil Rights laws in your state.
