Just discovered that our neighbours of 5 years have listed their home on Airbnb. They have decorated it as a party place with outside firepit, and built an outside viewing platform overlooking our garden (without planning permission and it breaks rules). First month occupants were 3 pleasant quiet men in the area to fit out a shop. But Airbnb listing of 3 bed house is for 7 people which would make it an HMO. We fear what will happen next, as this was a tranquil country road in Milton Keynes. We've lived here 35 years. What could we do to stop this?