I rented my 911S to a movie company for a week or so last year. They paid me by check & sent a 1099 at year end.
Most of the rest of my income is wages and such, no personal business currently, so I was prompted and created a personal business in turbo tax that rented my car to the movie company and declared the payment as business income. The expenses of the business we limited to things that were actually involved in my providing the car to the set for that time.
I also was prompted to declare a value for the car and Turbo Tax did a 7 day depreciation on the vehicle. In the end I don't think I incurred any tax liability for the $1000 of income I recieved.
I am not a Tax advisor, just sharing my solution. YMMV, of course...