And depending on the laws of your state, you may be breaking the law, giving notice or not.

In any case, I can't see it as affording any legal protection.  It's like those so called disclaimers on gals' sites that they do not sell sex.

(still not a lawyer)

I walked into a bank holding a gun, and stuffed money into a sack while yelling "I am not robbing this bank" loud enough to be picked up by the cameras.

It worked perfectly. LE and prosecutors watched the tape, threw their hands up in the air, said "what can we do?" and let me go.

If you were to call a provider and say you are not interested in sex, and you are recording this call, she will think you are a weirdo, and hang up on you.  

Hell, if my wife called me and said that, I would hang up on her too.

Even acknowledging that there *might* be something illegal about the transaction provides more evidence that there *is* something illegal going on there. I think the best way to act is as if there is nothing illegal about what you're doing - you're paying a woman for her time and companionship, and that's it.

But the best defense is only seeing reputable girls that will screen you well. If you end up walking into a sting - you're stung, no matter how well you've tried to cover your ass.