New sole traded vehicle advice

After taking early retirement in December after a lifetime on PAYE I'm intending to become a sole trader doing garden maintenance. My current car will be no good for transporting equipment so I need a van or pickup, but it will be my only vehicle so will be used for personal journeys too. All of my work will be local, so even if used 4 days a week for work the mileage will be low. My elderly father lives 130 miles away and I visit him once a week, so that will account for 90% of the mileage, even though it's only 20% of the actual use. Are there any mechanisms within AIA, expenses and self-assessment where this is factored or am I just stuck with mileage as the only method of calculating work versus personal use?

Hi ,
 

As you will be using the vehicle for private use, you have to exclude that part when claiming expenses or capital allowances in your tax return.  If you keep a record of your business mileage, you will be able to apportion costs based on that. Thank you .

Hi Thank you for the response, but it doesn't really explain the answer to my question. Is mileage the only metric that can be used? There's no nuance at all to acknowledge time over mileage? I'm talking about a van that I don't really want as my private vehicle and would only be buying because I need it's capacity for transporting waste and equipment 32 hours per week where the mileage happens to be local. I can't afford to own multiple vehicles so it would be used privately just 1 day per week for an unavoidable long personal return journey. Any piece of business equipment other than a vehicle would, presumably, just have its personal v business usage measured by time.