The best source I know of for the case law on LLC appraisal processes is Peter Mahler’s Business Divorce blawg.  In this post, Peter provides a brief but very information general discussion of the steps in this process.    Here is the link to his post:  https://www.nybusinessdivorce.com/2019/05/articles/dissenting-shareholder-apprais/how-to-initiate-a-fair-value-appraisal-proceeding-a-dissenters-checklist/