In general, you can use this approach unilaterally but you are going to have to teach the other side how to give in the context of negotiation.
Think about what you would want if you were on the other side and ask them to think about the same thing.
Write down the most you are willing to give a perfect counterparty and the least you would accept.
Ask them to do the same.
Say something like, “If later you decide to improve your offer, then I will not work with you because you lied on the first go-around, and I do not work with liars. Likewise you should hold me to the same standard of honesty.” Of course, you can find less harsh words than these.
Reveal what you wrote to each other simultaneously.
If you each offer more than the other would accept, and you honestly admit your imperfections, then you will come to an agreement.
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