It’s entirely understandable that you want to try to save money on something that you aren’t using, but it’s crucial to keep the vehicle insured. There’s no type of insurance policy that kicks in only when the car is being driven. It’s likely that a prospective buyer will want to test-drive the vehicle, and you’re liable for any accidents that may happen with your car, even if you’re not the driver. The safest thing to do is to keep coverage on your car until you’ve signed over the bill of sale to the new owner.
To learn about transferring your car title to a new owner, check out this article: How to Transfer a Car Title.