Over the last several years, accessory dwelling units — or ADUs — have become one of the fastest-growing housing opportunities in California.

Backyards across the state are being transformed into small homes that can generate rental income, house family members, or create long-term financial opportunity.

In many neighborhoods, properties that once had only a single home now have two.

And in some cases, even three.

For homeowners, ADUs represent something powerful.

They offer flexibility.

They offer additional housing.

And they offer the potential to significantly increase the value and financial performance of a property.

But despite all the excitement around ADUs, many homeowners still struggle with one impor ...