Most of us will be dealing with our parents downsizing, or stay put. I have being seen for the last few years families unsure and reluctant on sell or assisted their parents to downsizing. Families are instead building an adobe either on the garage or next to their own home.
I have been creating new spaces for aging in place since 2005 when I started working with clients in their own homes that became my motivation to assisted my clients and patients aged in place or transition to hospice.
You will need to do a little researched to find what your state permits, as well as paperwork needs, to assisted you with the Adus (accessory dwelling units).
Read more about at AARP.org.