Getting The Last Concession

[Jonathan Feliciano]

In @Brandon Turner's The Book On Rental Property Investing, Turner touches upon the art of negotiating a deal.

He says to "always get the last concession" when negotiating a deal for a property. The reason behind this is "if the other party realizes that every time he asks for something, he will need to give something, he will naturally shy away from asking for more."

What do you do when the seller denies your "last concession"? Do you walk away? Do you let them get the last concession? Do you offer an alternative demand? 

Is it really that important to get the last concession?

Looking forward to reading your responses.