I ask clients if they want their envelopes back.  Out of approximately 400 individuals I have one who wants them back.  There's a note in his file.  I imagine what his file cabinet must look like, considering that one page folded inside an envelope is 5 thicknesses of paper to store the information on one piece of paper.  He also enters the same number in several places on the organizer.  Mortgage interest can be found on the Sch C worksheet, the home office worksheet and the Sch A worksheet.