About 20 years ago, I traveled to Europe and the Caribbean and met people in foreign countries through an organization called Servas. This was developed to help world peace and human understanding by facilitating international contacts. The group screened applicants to weed out fools and charlatans, and then you could be a traveler, a host, or both. Bring your own towels, etc.
The rules were that you would stay, free of course, with a host in the foreign country for a maximum of three days, you were not to use the place as a crash pad but to spend time with the host family and - maybe develop friendships and greater intercultural understanding.
You had some minimal information about the person you stayed with before you made the advanced contact. I really enjoyed this - it is a wonderful experience. I had a brief but splendid affair in France, I learned to ask for details before going on a "little walk" with any Swiss, plus I had an encounter with Voodoo in Curacao.
Maybe an organization of opera goers could work like this: "45 yo Male Hetro, Engineer, into Bel Canto and Bergonzi, Have two recordings of Emila di Liverpool. Detroit area." Even if the person arriving is a fool, it's only for three days.
I remember that my chamber-music playing friends had a directory of people who were open to getting together for chamber music. They were listed by location and relative skill level (from "Professional" to "makes coffee and cookies") so that if you were traveling and really had to play your viola in the Brahms A minor quintet, it could happen.
P. S. My place is not available.