When double-booking occurs, there is a risk of major problems occurring during the user's stay. It may not be easy to provide an alternative room in the case of a single-family house type rental villa instead of a hotel or condominium type property where alternative rooms may be provided.
If the owner/operator of the property is not aware of the fact that double-booking is occurring, there is a high risk of major problems occurring among the people who have made reservations at the property. Such tragic events may have actually occurred in Japan and abroad, especially if there are no alternative facilities nearby when such double-bookings occur. There have been incidents outside Japan where an angry booker has destroyed building facilities and entered the inside of the building while other booking parties were staying.