Hypothetically, suppose your house is "appraised" at $144,000, but it would cost you 3 times that much to get a comparable house in a decent neighborhood. Then let's suppose a developer wants to develop the area, and the value of the land where your house sits after the development would be somewhere in the neighborhood of $1.5 million. You are offered a "fair" price of $445,000 which is three times the "appraised" value, but only a breakeven amount for you to replace the home, and less than a third of the true value of the property to the developer. You decide (as would be your right if private property rights mean anything) that the home is worth more than they are offering, and you refuse to sell. So the developer gets the government to come in and take your property for less than you are willing to sell it so that they can have it for their development.
It is always rather amusing when otherwise conservative people decide something is a "fair deal" for someone else's property. Private property is a fundamental right and principle of conservatism. For government to use eminent domain to take property from one private party in order to give or sell it to another private party is completely inexcusable.
I find it hard to believe that people here believe the local government at all about the appraised value.