Print the worksheet to paper or a pdf. Then go ahead and delete it. Save the printed copy for the day that property is sold. It doesn't really serve any purpose lingering around.
I code it to form 17 4562 only then I put a 99 for depreciation so it no longer calculates depreciation. Those then print out every year with the clients tax return, that way if they move or use a different preparer that tax preparer has that information. That great if you just print a copy and keep in your file, but in my office I have had them purge files including the back-up accidentally.