About Our Agency Our expertise and independence assure the best choices for you. Three generations of the Castle family have built Insurance by Castle from a one person business serving local community clients to a leading insurance provider in California. Today, Insurance by Castle provides a wide range of insurance services to a variety of clients, including both businesses and individuals. Our growth and success have been built on a track record of exceptional expertise, ethical professionalism, and unmatched client service. One of the greatest benefits we bring to you is our independence. Insurance by Castle gives every client the widest possible range of insurance providers, coverages, and pricing. This means we can, literally, find the very best choice for you — our valued client. Because we are independent, we are not tied to any one insurance company. — we work for you! This means we are free to seek out the best coverage at the best price to meet your particular, specific needs. And we do. We represent a carefully selected group of financially sound, reputable insurance companies, and are free to work with the company that offers the best coverage for you at a very competitive price. We are one of the largest independent insurance agency for residential rental property owners, apartment owners and property managers. Being an independent insurance brokerage, we shop all of our companies for the best fit for the property owners by rate and coverage.