These California homeowners paid millions to have ADUs built. The best they got were permits or port-a-potties, they say.

A Chula Vista construction company that pledged to disrupt the local market for accessory dwelling units — the granny flats that so many homeowners want to expand their living space, and so many elected leaders have pushed to help solve a critical housing shortage — is being broadly accused of fraud.

Instead of building the backyard homes known as ADUs, a new lawsuit says Multitaskr Construction collected at least $10 million from San Diego County homeowners and then did little more than plant portable toilets on the property.