Thanks for your question
As you will purcahse another vehicle as far as self employment is concerned you can claim expenses for travel in twp ways
1) Mileage method, which just allows you to claim 45p a mile (for the first 10,000 miles) and 25p amile thereafter for all business mileage (with the self employment) this just requires you to keep a record of all business milege undertaken
2) The actual method, which allows you to claim a % of the running costs (fuel car tax, insurance etc) and also make the same % claim on the vehicle itself as a capital expense.
This would require you to keep a record of ALL mileage AND business mileage so a percentage attributable to business could be established. And then for the price of the vehicle (which does not have to be commercial) then you can claim the capital allowance rate which is then restricted to reflect the business element.
And if you purcahse with a bank loan then you can also claim the same % of the interest charged on the loan or leae arrangement.
Please do let me know if you need me to expand further
No it can be either