To be honest, if you're paying an accountant then they should be earning their money by advising you what you can claim for in order to reduce your taxable income. As Rich says, the mileage allowance, 40p/mile for the first 10k miles, 25p/mile after that is a good place to start. But remember, if you claim the mileage allowance you cannot claim ANY other motoring expenses. As before you can claim a capital allowance on equipment used in the course of your trade. However, rather than writing things of at a fixed % over the years, you can now claim one off deductions, up to a total of £100k / pa (I believe).
Cheers
James
ps Rich - That S2 5 is gorgeous!