I usually love Zillow for shopping new properties and deals however upon trying to review an unscrupulous realtor I found that they are shielding Realtors using their premium service from some negative reviews. I've submitted eight different times honest and will tempered review of one specific realtor and every time there's a new reason they won't accept it. I'm just putting this out there be wary, they are known in some of the real estate forums to do this.