A one-stop source about multigenerational homes, laneway houses, ADUs, granny flats, in-law units, accessory dwelling units…
[this material may be somewhat dated, please look for newer posts about appraisals by searching the site -- ed.]
Link to Appraisal Journal paper published 2012: Understanding and Appraising Properties with Accessory Dwelling Units.
Executive Summary of an earlier presentation::
Guidance related to appraising properties with permitted ADUs:
Example of permitted ADU appraisal: