Do I need to buy insurance from the rental car company if I have my own personal automobile insurance?

That depends. Liability protection that you carry for personal injury and property damage will provide some protection while you are driving the rental car. Damage to the rental car would be covered under Collision and Comprehensive Coverage, if your policy has it. The rental car company may also try to recover damages for lost income while the rental car is out of service. Your auto policy may or may not protect you against this claim; the best way to know is to look at your policy or ask us to review it for you. Credit card companies often provide protection against these kinds of rental car claims so you should check there to see what the provisions and restrictions might be. Finally, you can purchase a Collision Damage Waiver - CDW - from the rental car company. This isn't actually insurance but a release from financial liability you might otherwise be charged with as a result of damaging the rental car. The CDW is expensive at $8 to $12 a day. This would amount to over $4,000 a year for very limited coverage. Still, if you do not have protection via your auto policy or credit card, paying the CDW over a few days may be preferable than being personally accountable for $15,000 or $20,000 or more to replace the rental car.