Some things to consider when deciding to build an ADU

1. Cost: Building an ADU can be expensive, and costs can vary widely depending on factors such as location, size, and design. In addition to construction costs, there may be fees for permits, impact fees, and utility connections.

2. Zoning and building codes: ADUs are subject to zoning and building codes, which can vary by city and county in California. These regulations can dictate things such as setbacks, height limits, parking requirements, and more, and may limit the location and design of your ADU.

3. Limited space: Depending on the size of your property, there may be limited space available for building an ADU. Additionally, if you are building a detached ADU, you may need to sacrifice some outdoor space or landscaping.

4. Tenant management: If you plan to rent out your ADU, you will need to manage tenants, which can be time-consuming and may require additional legal and financial responsibilities.

5. Neighborhood opposition: Some neighbors may be opposed to the construction of an ADU, either due to concerns about increased density or changes to the neighborhood character.

6. Utility costs: Adding an ADU to your property can increase your utility costs, as you will be responsible for providing water, electricity, and other services to both your primary residence and the ADU.

It's important to carefully weigh the potential benefits and drawbacks of building an ADU before making a decision. Consulting with a local real estate professional, builder, or architect can help you better understand the costs and requirements involved.