1. A computer-implemented method for classifying an existing loan secured by a property into one or more risk categories, the computer-implemented method comprising: retrieving a property estimate performed on the property, the property estimate used to originate the existing loan secured by the property; determining a time period when the property estimate was performed on the property; retrieving an automated value estimate of the property as of the time period when the property estimate was performed, the automated value estimate being determined using an automated valuation model (AVM); calculating, using a computing platform, a score reflecting whether the property estimate accurately reflected the value of the property as of the time period when the property estimate was performed, the score being calculated based on a comparison between the property estimate and the automated value estimate; and categorizing the existing loan into one of the risk categories based on the calculated score.