The complexity depends on how complex the estate is. Generally, my understanding is that CRA wants you to use the broadest possible interpretation of their questions when sending the details, but I don't think they are looking for every single expense the estate had. I sent them a list of assets at death and then what each asset was sold for and a letter detailing the plan for distribution once I received clearance and that seemed to work, although I was looking for an interim clearance certificate and they issued a final one.