In May 2017, Susan Brundage started Brundage Art Advisors LLC with her sister Patricia Brundage, specializing in art advising, appraisals and estate planning. They have appraised for estate planning purposes several private collections as well as the artwork by artists who have wanted to know the base line value for their own artwork. Ms. Brundage is a certified member of the Appraisers Association of America (AAA) in Post-war and Contemporary Art and Chair of the Association’s Membership Committee and a former member of the Board of Directors.  At the 2017 National Conference of the Appraisers Association of America she was awarded the President’s Award for outstanding service to the organization.

In 2019, she represented the AAA in Seoul, Korea at the KAMS (Korean Arts Management Service) conference on Authentication and Appraisals. She is also a former member of the Personal Property Resource Panel of The Appraisal Foundation based in Washington D.C. From 2007-2017, Ms. Brundage was the Director of the Appraisal Service of the Art Dealers Association of America. She was a freelance appraiser with the ADAA from 2001. From 1972 to 1997, Ms. Brundage was the Director of Leo Castelli, the world-renowned gallery that exhibited the most important pop, minimal and conceptual artists.

Over the 25 years at the gallery, she became close friends with the artists and many of the collectors who bought from the gallery. These friendships with the artists and her knowledge of their artwork have created the opportunities to do the estate planning appraisals for several of the artists and collectors.