A system is engineered to facilitate calculation of predicted perils connected with a ridesharing vehicle. The system facilitates premium endorsement that provides higher coverage than is provided under conventional products and allows drivers to work directly with their personal lines insurer in reviewing their coverage and filing a claim in the event of an accident. The subject matter facilitates higher limits while including a post-policy period audit that allows a reconciliation of high-use or high-risk driving with appropriate retroactive rate adjustments. The system also facilitates retroactive rate adjustments that would compare a policyholder's time/distance driven or collected telematics data (including time or distance driven in each driving period) to the group average or other historical underwriting data.