What about rental car, there is no option for it, do I consider it as a lease or the car isn't mine ?

You can deduct rental car fees used solely for business plus gas costs. This is especially true for short term and travel purposes. You can't take Standard Mileage because that amount includes an allocation for depreciation. If used only partly for business, the safest way would be to treat it as a lease so as to only claim the business percentage.