Cities around the world are cracking down on Airbnb rentals, affecting both hosts and guests. Regulations vary from place to place, with some cities implementing restrictions such as only allowing hosts to rent out their primary residence or capping the number of nights a property can be rented. These changes are happening due to concerns over affordable housing, property values, and community disruption. Hosts and guests are advised to check local regulations before booking or hosting through Airbnb.