Why Spillover cost of the production of large expensive houses?

Spillover costs in the production of large, expensive houses often arise from negative externalities that affect the surrounding community and environment. These can include increased traffic congestion, strain on local infrastructure, loss of green space, and potential impacts on property values for neighboring homes. Additionally, large developments may lead to social inequalities, as they can contribute to gentrification and displacement of lower-income residents. Overall, the costs associated with these external impacts are typically not reflected in the market price of the homes themselves.