I am really sensitive to the smell of smoke on clothes hair etc. You mentioned a smoker staying with you. Is this person smoking in your home? I have a strict no smoking policy for our house and cars. My DH is actually a smoker although he never ever smokes at home on our property. He also changes as soon as he gets home if he had a cig that day and once the baby comes will be washing his hands etc before touching her when he gets home.
Is it possible to find other accommodations for your guest? You can't tell another person not to smoke but you can request that your guest not smoke in your home, vehicle, or around your child. It may be a bit more work but personally I would find myself doing a bit more laundry and cleaning if the smell was too bad while the person stays.