Don, I don't think around 8 house concerts lasting possibly 3 hours is quite the same thing as a doctor's office or day care, which are open on a regular basis, and have paid employees.
The above are businesses. Hosting the odd house concert for no pay is not operating a business.
Here's another quote:
Q. What are public accommodations?
A. A public accommodation is a private entity that owns, operates, leases, or leases to, a place of public accommodation. Places of public accommodation include a wide range of entities, such as restaurants, hotels, theaters, doctors' offices, pharmacies, retail stores, museums, libraries, parks, private schools, and day care centers. Private clubs and religious organizations are exempt from the ADA's title III requirements for public accommodations.
I can argue that an occasional house concert which is open to the public, for no monetaty gain of the host, does not make a private home a 'public accommodation'. I can argue that even the most craven lawyer wouldn't take such a case.
What I think makes the most sense is for GUEST or GUEST's friend who hosts the concerts to call the experts and ask them. I don't think ANYBODY will say that's not the best idea.
By the way, the house concerts I go to here ask for a 'suggested donation', and as far as I know, the host never touches the money.