Most of the cost segregation studies that cross my desk are lookback studies, where the property owner and CPA have realized long after the building was put into service that cost segregation could be effectively applied to the building. Although lookback studies are beneficial, the optimum time to apply cost segregation is as soon as one of these trigger events occurs, so accelerated depreciation occurs immediately rather than catching up later. Here are 6 events that create the opportunity to apply cost segregation or tax deferral