@mygiftconsult
You need to start by carefully reading chapter 4 of IRS publication 463.
https://www.irs.gov/pub/irs-pdf/p463.pdf
At least one of the experts you quoted was mistaken. The statement "You can only use actual expenses if you used this method THE VERY FIRST YEAR you placed the car into service" is incorrect, it is actually the opposite. The IRS states
If you want to use the standard mileage rate for a car you own, you must choose to use it in the first year the car is available for use in your business. Then, in later years, you can choose to use either the standard mileage rate or actual expenses.
The IRS also states
If you want to use the standard mileage rate for a car you lease, you must use it for the entire lease period.
Assuming you used the standard mileage method in 2019, then you were required to use the standard mileage method for 2020-2022. However, if you bought the car off lease in 2023, then you may use the actual expense method for 2023. If the vehicle is not used 100% for business, the actual expense method requires that you keep track of all your business mileage, your total mileage, and all your expenses (fuel, repairs, maintenance, interest, depreciation, registration fees). You deduct the percentage of total expenses corresponding to the percentage of business use. If your mileage log shows you used the car 60% for business, you can deduct 60% of the expenses. Note that if you are audited, and can't prove your expenses (such as, you don't have all your gas receipts) you may lose the deduction.
The purchase price of the car is not a deductible expense. Instead, you claim depreciation based on the cost. That's how you recover the purchase price. You can include interest on the loan (subject to the business percentage rule) but you must be able to separate the interest portion of the payment from the purchase price portion of the payment. Sales tax is included in the purchase price and depreciated. Registration fees, license plate fee, etc. may be expensed, subject to the percentage rule.
Your problem will be determining the correct basis for depreciation. When you leased the car, you essentially "bought" the first 25% or 50% of the car. This should be specified in your lease agreement. Let's say that was $20,000. Then, for 2019-2022 you used the standard mileage method for your car expenses. The standard mileage method includes about 27¢ per mile for depreciation (although the exact figure varies from year to year). Let's say that over 4 years you claimed 50,000 business miles, so that's $13,500 of depreciation, so your adjusted cost basis is now $6,500. Then, you paid another $22,000 including sales tax to buy the second half of the car. Your basis is now $28,500. That's how you must calculate your current cost basis so you can calculate the amount of depreciation you can claim as an expense on your 2023 tax return. If you can't prove your prior mileage (because you don't have records), then any deduction for depreciation could be disallowed if audited.
You may want professional assistance this year if you really want to use the actual expense method, to get the calculation right. Remember that with the standard mileage method, the only thing you have to prove if audited is your business miles, usually from a diary, log book or expense tracking app. If you want to use the actual expense method, you must be able to prove every expense, along with all your business mileage, and also prove your prior business mileage deductions.
Fines for breaking the law are never deductible business expenses (such as a speeding ticket), neither would be traffic school to get your license back. If you are a commercial driver and a CDL is required for your business, you can probably deduct the additional cost of a CDL renewal compared to the cost of a standard drivers license.
