@Susan612 “If they would be willing to add filters for allergies and fragrance sensitivities.”
It would be impossible for any host to advertise their space as free of allergens and guarantee it, for a whole range of reasons. Some examples to consider:
Airbnb makes it very easy for any guest to bring a pet to a non pet listing due to their ridiculous assistance animal policy, often times unbeknownst to the host. So there will be pet dander in a listing advertised as ‘no pets’.
Guests may use strong fragrances that can linger in a space for days. Some may bring in their own scented products like air fresheners or scented candles, or cleaning products, if a longer stay.
A home and everything in it will off gas. Hosts may not have control over what products their cleaning companies use, and harsh products are needed in these pandemic times.
Those are just a few scenarios. I doubt you’ll ever find a host who will advertise their space as allergy free, as again, impossible to control and guarantee, and doing so only opens the host up to trouble.