Here is an easy way:

  1. Install Case Add-in Manager
  2. Using the Add-in Manager, install Batch Export Family RFA’s tool (I am running v2012.11.13.0)
  3. Open a Revit project and run the tool
  4. After families have been exported, you will be presented with an error message that tells you which families are in-place (see below).

NOTE:  The Case exporter also creates folders for each Category as it exports.  Nice.

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