Here’s a good summary of the insurance aspects of the ride services.
https://wallethub.com/edu/ridesharing-insurance/13884/
Metromile is really interesting. You pay a monthly fee of $20 and then about $.03 per mile. They work with Uber and deduct the miles driven for Uber each month and bill you only for personnel use. Since I rarely use my second car, its insurance dropped to $20 per month. For my Uber vehicle, I pay about the same I did before I started doing Uber.