It doesn't matter so much what you tell them so long as you are willing to reject a lowball offer and ask for more. If they are going to negotiate with stupid

It doesn't matter so much what you tell them so long as you are willing to reject a lowball offer and ask for more. If they are going to negotiate with stupid tricks and use information you give them adversarially, feel free to drag out the interview process at their expense. Once they make the offer they've revealed their intention to hire you. If they had made you a fair offer the first time around they wouldn't have to worry.