@Catherine232
I wouldn't feel 'a right cad' under any circumstances when endevouring to figure out if my home is appropriate for guest needs, more so as a live-in host.
For this reason I've resisted Instant Book from day one of its introduction, which I find contra the original ideal of 'home-share' and finding the right 'fit', etc.
Without IB, the process of Inquiry can be as thorough as need be. In six years I've dealt with a little under 1,200 Inquiries. My conversion rate from Inquiry to bookings has remained remarkably consistent. I've accepted about a third. The remainder is roughly divided half-half between those that I do not feel are appropriate for my home, and a third who decided it was not for their needs.
I've had to deal with a number of medical conditions. The ones who have been up front were the ones with disabilities, necessarily so since my listings emphasize it's not a ground floor flat and no elevator in Amenities. Conversely, I discovered those with physical ailments have been least forthcoming, and this has led to some difficulties during the stay.
The most extreme condition I've had to deal with is Lupus with OCD. (But this turned out to be a very warm engaging lady with a young daughter, to whom I became a virtual servant for the first week till husband/father turned up, and extended one week into three week stay.)
The worst experience was with a psychiatric condition, that turned out to be a clinically diagnosed paranoid. It was made worse as an undisclosed 3rd Party booking by his flatmate. It became very uncofmortable for both me and others in the flat, that I duly had to ask the Guest to leave, the only one in near 400 bookings. The booker took revenge with an awful Review and Star Ratings which also led to a 5-Day 'pause' to the listing. It took me a month and considerable effort to get Airbnb to delete the Review & Ratings based on infringment of 3rd Party Booking rule.