The environmental and water laws in California are strict, and vary from county to county and even from city to city. Because of this, mobile car wash businesses are monitored for compliance with all appropriate regulations regarding water use and disposal of wastewater. In California, each municipality licenses mobile car washes, but the state requires car washes to be registered with the Division of Labor Standards Enforcement (DLSE) as well. You must obtain the appropriate licenses and permits at a local level before you can apply for a mobile car wash license with the state of California.

Register a fictitious business name or DBA (doing business as) with your local County Clerk's office. Additionally, obtain a business license and tax permit according to the rules of the county and/or city where your main office will be located (i.e., where you park your trucks, take calls, maintain accounts).

Contact the local water or wastewater management authority and apply for the permits they require of mobile car wash businesses in your area. For example, you might need an industrial wastewater discharge permit, a water usage permit or similar depending on the rules governing each specific municipality.

Purchase a surety bond for $15,000 from a company licensed to do business in the state of California. This bond should be payable to the people of the State of California and must be submitted on official forms.

Submit a completed Car Washing and Polishing Registration Application to the California DLSE. Included with your application must be the appropriate registration and assessment fees, a copy of your fictitious business name statement, local tax permits and local business licenses, your surety bond and proof of your compliance with local municipality regulations or local municipality permits.

Provide proof that you are exempt from holding workers' compensation insurance and employer tax ID numbers due to not having employees, or if you will hire employees, you must provide proof of compliance with insurance and tax requirements for California employers.

Make a copy of your complete application and send it along with IRS Form 8821 to the Internal Revenue Service, giving permission for the IRS to disclose your business tax information to the DLSE. Once all of your information has been reviewed and verified, you will be issued a Car Washing and Polishing License to operate a mobile car wash business in California. If your application is denied, you will be notified of the reason and may have to reapply or provide additional information.