A method of purchasing and selling insurance includes transmitting property information, having the property information analyzed, modifying at least one quotation calculation underwriting rule based on the analysis of the information, creating an insurance pricing model based on the modified underwriting rule, transmitting and receiving the insurance quote, and purchasing insurance via computer. A method for modifying insurance coverage including transmitting property information and existing policy information to a first insurance provider, generating a document directed to a second insurance provider authorizing cancellation of the existing insurance policy and directing the second insurance provider to remit a refund payment.