My DS has always been really challenging like that. A real negotiator. He gets the nickname "attorney" or "litigator" wherever he goes. It was exhausting. It took me awhile to realize that it worked better with him when I didn't explain or negotiate -- when I was just as clear as can be. Example: he interrupts when I am on the phone. I say, can't you see I'm on the phone? Well, that"s actually not that clear. My daughter understands that type of communication. To this day, my son does better if I say something plainer, such as "don't talk to me until I am off the phone!"

This really hit me when I was reading "how to talk so kids will listen, etc." The tips in that book generally did work for my daughter. She did appreciate knowing I was listening. My son just thought that any expression of empathy was an invitation to negotiate. It never worked. I did eventually use the abhorrent but effective "1-2-3 magic" technique with my son. I still find that he does better with
Limits that are black and white.

Btw, while I am talking of parenting books, the very best one ever that really does help with a huge number of things is "Playful Parenting." it is great and could be a sanity saver.

Also, I hope I didn't give the impression that it's like West Point around here with my son. He is a totally delightful kid. Strong-willed, and he has endless energy for sparring and negotiating, but we also have a ton of fun together.