How long it takes to receive the job offer letter from the City of Los Angeles Departments? These basic sample offer letters consist of "core" data that should be included in an offer letter.More categories coming soon! No. You must complete a County of Los Angeles Job Application for a job opportunity that is open for filing. The answer to your question, regarding whether you can back out of the Offer Letter, is likely "Yes. Just write your address where you can be reached. COMPLETING YOUR APPLICATION: a. Apply to Shipping and Receiving Clerk, Administrative Assistant, Clerk and more! Applications for most jobs in Los Angeles County are accepted through our online Job Application System. What is an offer letter for employment in California?