The cost of error omission insurance will also vary based on a number of factors but primarily on the merit of the policy holder. An underwriter will examine the claims history and other documents such as contracts in order to determine the risk involved in covering a potential client. Exposure to limited may be limited with comprehensive contracts. Also, it is best to purchase a policy before an incident, usually before the business or professional begins to provide a service to clients. This will ensure better rates as well as better coverage for the policy holder. Errors and Omissions Insurance