PPO is a very large category. Your policy may vary. I don't think a policy can cover ALL.

Usually, doctors won't ask you if you can afford. (well, you can afford $5k, right? But you will not be happy)

Ask your doctor first. If he is not sure, he will recommend you to confirm with insurance company.

It is always good to play safe, esp. you are dealing with (1) insurance company; (2) doctors; (3) ...