Customer service asked me to assist. I am a member of the State Bar of California, the U.S. District Court for the Central District of California (Los Angeles, Ventura, San Luis Obispo, Santa Barbara, Orange, Riverside and San Bernardino Counties), and the California and National Associations of Realtors.
The insurance you want to obtain is "product liability insurance." A lawsuit for product liability cannot be avoided by a customer liability waiver -- especially because there is no guarantee that the customer will be the person injured by your product. Any third-party rider/operator can sue you for their injuries, and your contractual waiver would be useless to protect you from a damage claim.
Also, if the operator is under the age of 18, then that person could have an independent claim against you, despite the waiver of their parent as part of the purchase of the vehicle.
Bot***** *****ne, if you don't have product liability insurance, then you are at extreme risk of legal action, should your product injure an operator (or, a bystander).
I hope I've answered your question. Please let me know if you require further clarification. And, please provide a positive feedback rating for my answer -- otherwise, I receive nothing for my efforts in your behalf.
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