If Google Search Console shows Missing field additionalType on your property pages, this is a warning, not an error. It does not block your listings.
Why this happens. In Google’s vacation rental structured data specification, additionalType is on the recommended list, not the required one. The required fields for the VacationRental type are containsPlace (with occupancy), identifier, image, latitude/longitude, and name. HomeRunner property pages include all of these required fields.
What this means for your listings. A page missing only recommended fields is still valid. It stays indexed, remains eligible for rich results, and the warning does not block Google Vacation Rentals listings. Recommended fields are worth adding over time because they enrich how Google understands the listing, but nothing is broken and no action is required.