The Dunphy’s neighbor has a new boat that they leave in the driveway. Many of the family members are impacted by the visibility of the boat. This represents spillover effects and mean that an externality is present in the market for boats. Some family members see the boat as having a positive externality. Others see the boat as having a negative externality. As there is a relatively low number of people impacted by the boat (the Dunphy’s and other nearby neighbors), Coase theorem suggests that an efficient outcome can be negotiated. But will the Dunphy’s be able to get to it? Claire is immediately interested in finding regulations that restrict how residents can store large property like a boat. Many communities, especially home owner associations (HOAs), have rules pertaining to this situation. These rules are designed to lower the transaction costs associated with these externalities by providing a standardized process for dealing with conflicts between neighbors that settles disputes, thereby increasing the likelihood that an efficient outcome is attained. However, often these processes can end up creating problems themselves. What happens, for example, if the neighbors get together and decide that it’s OK to store the boat in a visible place? If they do and the enforcement agency requires a change, it can make things worse.

See more: Coase theorem, externalities, negative externalities, positive externalities, private benefits, private costs, property rights, regulation, social benefits, social costs, spillover effects, transaction costs