Congress needs to crack down on mortgage bankers and brokers if it wants to head off the problems created by dubious appraisals, a trade group representing appraisers has warned. “Large volumes of mortgages originate through these institutions, and to this point, their appraisal practices have generally gone unchecked. This is an area that should be further explored by Congress,” said Gary Taylor, president of the Appraisal Institute, in testimony