Autodesk Design Review is free software that you can use to view, print, markup, and measure AutoCAD drawings. I am going to show you how to compare design changes with it.
Open a DWF in Design Review and select a sheet that you want to compare.
Go up to “Tools” and select “Compare…”
Browse to find a DWF of the same drawing set, created at a different time. Then select the same sheet that you currently have open in Design Review.
If you want, you can change the default colors for things that were deleted or added between the sheets.
Final result is essentially an automatic markup of the DWF sheet showing what is new and what has been deleted.
(the sheet shown above was compared to a completely different sheet to show exaggerated differences)