The only way you'd do it would be a rental deal. Any of the car rental companies will do this, but my experience is that you'll get a better deal from a small local company. Another thing you might try is to see what kind of deal you can get through your airline. You might expect to pay about £150 per week for a small medium car. Say £600 for four weeks to include everything except fuel - depreciation, RFL and insurance. Must be cheaper than taxing and insuring a car for a year.
Hope this helps