@Aaron279you can ask the guest if they have a disability (but not what it is) and what task the dog (only species that can be a SERVICE animal other than the rare mini horse) is trained to do. The task has to directly mitigate or support the disability. So a blind person's service dog guides them, a deaf person's service dog alerts them to sounds, a wheelchair user's dog picks things up off the floor or opens doors. If the deaf person's dog is trained to pick things up but doesn't alert to sounds and the person is able bodied, that does not qualify as a service dog. If the dog is with someone who is not disabled but they claim that it is owned by a disabled person who is not present, that is not a service dog.
If the animal is not task trained or the person does not have an ADA recognized disabiltiy then it might be an ESA (emotional support animal) but it is not a service dog. You are 100% justified in 100% excluding it from your premises if you don't want it there. ADA does not cover ESA. Airbnb allows ESA but not if it puts your family at risk.
All service dogs and ESa can be required by you to have supervision of the owner or their agent 100% of the time.