If you mail your inmate the Power of Attorney document, he can go to the unit secretary and have it notarized when a notary comes to the institution (usually a couple times per month for this very reason).
https://www.inmateaid.com/ask-the-inmate/please-explain-the-costs-associated-with-the-inmate-response-letter-service-8029#answer
Accepted Answer Date Created: May 03,2016