Derby Insurance Services, Insurance You Can Trust, Service You Deserve. Located in Souix City, Iowa, Derby Insurance Services is a full service insurance company specializing in life insurance, health insurance, auto insurance, business insurance, home insurance, annuities and crop insurance. You deserve the best the industry has to offer and our professional staff will always find the best insurance available to fit your needs. We work with several major insurance companies giving us the luxury to shop around for the best rates and coverage. Let us do the heavy lifting for you.