Introduce the car into the business as usual, claim capital allowances but make adjustments for personal use. I see no problem that the car is in her husband's name.
Would it be worth it Stuart? Remember if the mileage is claimed then you can't claim any other motoring expenses including fuel, repairs, insurance, capital allowances. Having said that I don't think there is any restriction on who can claim it unless actual expenses have been claimed in the previous year.
Also remember that if the vehicle is purchased on a hire purchase agreement then a claim can be made for the business proportion of the finance charge as well (assuming you do not go down the mileage allowance route).
