Rental car insurance has 4 main components, they include collision, personal accident, liability, and personal effects. If you have the OPCF27 endorsement on your auto policy, you can port your existing insurance to avoid paying for personal accident and liability insurance. If you have collision insurance on your policy, you can port that as well. Personal effects coverage is covered by your home insurance. If you don't have the right endorsement on your policy, check your credit card, it's possible they offer collision coverage, so the only coverage missing is liability and accident insurance which you should pay for.