So you get your buddy to make you a low-ball offer on your property that you'll definitely refuse so you can pay less taxes. Then you do the same for them.
Meanwhile, that person you don't like? Make a ridiculous offer on their property to either force them to move or suddenly have to pay absurd taxes.
You'd value the property based on the max offer the person had gotten, not the minimum.
This gives the person you don't like the option to take your ridiculous offer and stick you with the absurd taxes. Sure they have to move, but they now have the resources to do it.
Meanwhile, that person you don't like? Make a ridiculous offer on their property to either force them to move or suddenly have to pay absurd taxes.