Building Design Suites as of 2014 have a built-in uninstallation tool (very handy).
For (some) 2013 suites:
How to perform an automated uninstallation of the AutoCAD Design Suite 2013 family of products
You could also go the “manual” route:
How to remove all Autodesk products from a Windows system
2013: How to Complete a Clean Install [Uninstall] of Revit products
2012: How to Complete a Clean Install [Uninstall] of Revit products
revit in plain english: Building Design Suite 2014 Unistaller