While a financial expert may be retained to proactively complete a lifestyle analysis in a divorce case, one might also be retained to do a rebuttal report focused on the analysis of an expert retained by opposing counsel.
The process is no different than if the lifestyle analysis is being done proactively. Income and expenses are tabulated, categorized, and allocated using the methodology I describe on this blog and in my book, Lifestyle Analysis in Divorce.
It is likely that the expert will need to compare his or her lifestyle analysis to the one done by the opposing expert. However, this is not always possible. It is not uncommon for an opposing expert to provide a lifestyle analysis that includes little explanation. It is not uncommon that the lifestyle analysis is done in a way that makes it impossible to deconstruct the analysis or point out errors in methodology or logic.
It is most important that a forensic accountant be able to thoroughly explain his or her own analysis and the basis for the opinions. If he or she can adequately support his or her own opinions, the ability to explain the faulty analysis of the opposing expert will become much less important.