Grow the Pie by Timing Payments

Good negotiators find ways to increase value by making deals that give each side its high priorities while making concessions on that party's low priorities. 

I like to call this "positive-sum" negotiating, while some others like to call it "integrative bargaining" or "problem-solving negotiation." 

Whatever one calls it, a common way to do it is by considering different ways to time payments of money.   Karass gives short examples.