If you feel that the 3 day limit to your rental car allowance is not fair, you should try to negotiate more days with the at-fault person's insurance company. It could be that 3 days is all that the driver's policy allows for since your car was determined to be a total loss.

According to the consumer guide for auto insurance by the Ohio Department of Insurance, if a car is declared totaled insurance companies might pay for a rental car as a courtesy, but are not required to do so by state regulations. If your car was being repaired, the other person's insurance company would pay for rental car costs for a reasonable amount of time.

If you were going against your own insurance policy, you would have to have rental reimbursement coverage in order to receive rental car compensation. Also most policies like this have a dollar amount limit for rental payments.

Unfortunately, Ohio state laws do not find a rental car as part of the "making it whole" principle for totaled vehicle. I suggest trying to negotiate with the insurance adjuster to see if as a courtesy the insurance carrier will provide you with a rental for more days so that you might find a replacement vehicle for the one their policyholder totaled.