Well, a lot of people don’t see any moral issue here. But thinking about your query and thinking about it for myself just crystalized my thought on the matter. So here is another view.
Last year we were working on plans for a sort of mini-barn as a workshop area, and our designs included adding a second floor, to be used for an Air BnB, for income generation. I loved the idea of designing and maintaining a pleasant comfortable clean space for travelers. But after drawing up plans and the materials list, we found that even as a total DIY the materials were over what we could currently fund, and we set the idea aside.
Also I just commented on another query here
“working and living with two gay men” a story of how I first realized something is very wrong with sodomy.
But not just sodomy, but all sins against chastity are especially repugnant to God.
And now I realize, Air BnB is never going to be a plan for us. Perhaps if it was a separate rental property. But I don’t want any kind of mortal sin in happening in my home. Would Our Lady have had had anyone under her roof acting in mortal sin in her Nazareth home where the angel of the annunciation came to her? Would the Apostles have had a home they rented out to just anyone while they were off evangelizing? No, I don’t think so. We Catholics have hearts and bodies consecrated to the Lord and we don’t want our home to be a place where mortal sin is going on.
We had young grandchildren here recently and I came in the room to see they had on a pokemon show where someone was stabbing the cartoon creature over and over and blood was splurting out everywhere with each stab. Oh, no! Not in our house. What’s ok at their home is not so here! Same thing with magic-arts or demonic-happening shows, and a lot of other stuff. TV and computer is going to be real limited here at this house. We will just have to play more games with them if they are bored with our limits.
So no strangers from unlimited places staying here. Also I do think attempts to limit one’s “openness” to just anyone coming to your home will invite troubles and possibly persecution from the broader culture.
So there doesn’t seem to be a way to make this a reliable money-making deal AND impose some control over who stays in your home. Witches casting spells or hexes, or sage-“blessing” their room? Not to mention other mortal sins happening under your own roof? I see no way to screen that, so Air BnB is not happening on our property.
I am saying this about the Air BnB in my home as a Catholic because I have a choice. We are working on other ways to increase income. Some people who are running a BnB in their home really need to, and they don’t currently have another choice. So I understand. We all do what we can in the situations we are in, and we change our situations as we are able to.