BobKamman
Level 15

As @TaxGuyBill says, with a clarification I have added,

"Your Asset Entry Worksheet should show the ACTUAL value original basis of land, the ACTUAL value original basis of the building, and 'prior depreciation' that SHOULD have been taken. Nothing besides that for Asset Entry Worksheets."

I don't think Form 3115 is intended to convert sow's ears into silk purses.  I wouldn't file it anyway; the Accounting Police have worse blunders to patrol.  I would file amended returns for all open years, if another $9,500 or so in depreciation deductions would make a significant difference.  Then I would tell the client to expect to pay tax on recaptured depreciation, even if not claimed, when the bulding is sold.  The client can avoid this by dying first.