We are in the fortunate position of being able to buy a house for my parents in law to live in. They wanted to move back to England but didn't have enough money of their own to buy somewhere nice close to us. We have therefore offered to buy a house which they can live in. They are both heavy smokers (30+ a day each). The idea would be that it's an investment for us. However our daughter has asthma and I am worried about 1) her being able to even visit the house and 2) how badly the smoking will have affected the house when it comes to selling it on.
Is it unreasonable to expect them to smoke outside or even just isolate their smoking to one room?