Can I use two cars for business deduction. One car by standard deduction and other by regular?

I am self-employed, my wife is a w2. I have a honda civic 2003 that I use for my business. My wife has an Infinity G37 that she uses for herself. I deduct my business mileage on Honda Civic by standard deduction method. My question is,

  • Can I purchase my wife's car in the last week of December, use that car only for my work purposes?
  • Can I put both cars as business vehicles, deduct Honda civic expenses by standard deduction and Infinity's(which I am putting in use in last week of December) by the regular method and take advantage of the bonus depreciation?

Please advise. Thank you