Yes, you should report your expenses related to your car-sharing business, as well as the income reported to you on Form 1099-K.

As an owner renting your vehicle, you are considered self-employed and must report your business on Schedule C (available in TurboTax Self-Employed Online).

To offset your income, you may report any related business expenses. In the case of car-sharing, Vehicle Mileage is probably your largest expense. You can either take the standard mileage deduction (54 cents per mile for 2016) or your actual expenses. Substantial record-keeping is required to deduct vehicle expenses. TurboTax will walk you through these options and help you choose which is best for your situation.

This article may be helpful: Tax Tips for Uber, Lyft, Sidecare, and other Car Sharing Drivers

The easiest way to find this section of TurboTax is to use the Search box at the top right side of the TurboTax header. Click on the magnifying glass, type in "schedule c", hit Enter, and click on "jump to schedule c" to go directly to beginning of this topic.

Or go to My Account >> Tools >> Topic Search. Type in "schedule c", then click the topic in the list to go directly to the start of this section.

You cannot use the standard mileage deduction (of 50 something cents)  for Turo. That deduction is only for Lyft/Uber drivers and mileage deductions if you own a business.  Turo is not considered as ride sharing but rather as "car rental". For Turo income, you can only claim the expenses for maintenance, repairs, car washes, car cleaning. But i am not sure if you could claim the miles you put on the car when you drop off the car or pick up from a renter, or the miles you put to take it to carwash. 

I believe you cannot use the standard mileage rate for Turo. The standard mileage rate includes depreciation of the vehicle, insurance, repairs, maintenance, gas, etc. However, when you rent out your car your customers pay for their own gas and by using the standard mileage rate you are in a way claiming a deduction for expenses you did not incur since the gas portion of the standard mileage rate was covered by someone else. 

What about if the "gas" is purchased by me rather than the guest?

One of my Teslas on the platform has free supercharging included, meaning the guest does not pay any charging costs. It gets billed to my card directly when they plug in. Would that qualify?

@Pkmmte 

Yes, you may use the standard mileage rate, if you are paying all costs.

Hi, what type of business should we file if we are renting our car through Turo?

You can write off a host of things. For example if you’re having a dinner and you’re discussing your business that is a write off.  You can write off mileage to drop the vehicle, mileage that the renter puts on the vehicle You get to write off a portion of your house expenses because your business, or rather you are self-employed your offices in your home. There’s a lot of things you can write off when you’re self-employed.

You are self-employed. You can write off a lot of expenses

Report your income and deduct your expenses as self-employment income, as super helpful Community member @Cahoney1 suggests.

Because you personally hand over your car, you are providing a service. That's considered self-employment income.

Learn more about what you can deduct at: Reporting Self-Employment Business Income and Deductions