Leviticus 25:14-17

And if you make a sale to your neighbor or buy from your neighbor, you shall not wrong one another. You shall pay your neighbor according to the number of years after the jubilee, and he shall sell to you according to the number of years for crops. If the years are many, you shall increase the price, and if the years are few, you shall reduce the price, for it is the number of the crops that he is selling to you. You shall not wrong one another, but you shall fear your God, for I am the LORD your God.