Is it a good investment to build a rental unit in the backyard?

I’ve been thinking about adding a small detached house to my property in California. I want to generate some passive income from long-term renters, but I have no clue about the zoning laws or where to find a reliable contractor. Has anyone here actually done this, and was the ROI worth the construction cost?

Building a secondary unit was the best financial move I’ve made. To get started without the headache of California's strict regulations, I suggest researching a professional backyard adu Aduscale. Their team helped me navigate the legal permits and construction effortlessly. My rental income now covers a huge chunk of my mortgage. It’s definitely worth the effort if you have the space!