For a vehicle used exclusively for business, you can use the standard mileage rate or the actual expense method. The standard mileage rate includes allowances for fuel, maintenance, repairs, insurance, and depreciation. The only expenses you can deduct on top of the standard mileage rate is tolls. This has the least record keeping burden.
Or you can deduct your actual expenses. This includes the lease payments, fuel, repairs, maintenance and insurance. You need to track your expenses over the course of the year. If the vehicle is used 100% for business, you don't have to separately track your mileage, but if you also use it for personal use, you must track your milage and only deduct the percentage of expenses equal to the percentage of business use.
Also, the standard mileage rate only applies to vehicles under 6000 pounds unloaded gross weight. There are some other rules governing the decision of standard mileage rate or actual expenses. All these rules are covered in chapter 4 of publication 463, https://www.irs.gov/pub/irs-pdf/p463.pdf
It is frequently stated that the standard mileage rate is more favorable for most vehicles, however, you would have to make this determination yourself based on the cost of the vehicle and how many miles you expect to drive.
