How much does it cost to build an apartment on top of a house in NJ?

The cost to build an apartment on top of a house in New Jersey can vary significantly based on factors such as location, design, materials, and local regulations. On average, homeowners might expect to spend between $100 to $300 per square foot for construction, leading to a total cost ranging from $100,000 to over $300,000 for a typical project. Additionally, permits, utility upgrades, and potential zoning issues can further influence the overall expense. It's advisable to consult with local contractors for more precise estimates based on specific plans.