How to not get manipulated

They are focused only on what they want on a specific end result. Regardless of you, of ethics, they are looking for nothing but their goal.

Manipulators are trying to dominate the conversation but when you ask a simple question, you flip the roles. 

Counter: "What other options do we have?"

"you are certainly confused with the offer, but believe me, at the end of the day, you will feel that you have made a great deal" - often used by sellers to sell you the stuff you don't want or need.
or "you seem to be angry"

Counter: "Why do you say that?" 

"This car is just perfect for you" or "you need to exercise more"
oh really?
Counter: "How do you know?" 

"Can you answer only this one simple question?"
Counter: seek third party / witness / lawyer

"Sure, absolutely, the moment my lawyer gets here"

A picture is worth a 1000 lies: Using false pictures to create false childhood memories.
If it was a while ago and lots of emotions, we take creativity, imaginations, we can use some other memories from other events to fabricate the things.
Counter: be excessively critical; use deception indicators (to form your own opinion based on facts)