H&W - vans and cars, his and hers!!!

Wife is [sole trader] employer with two shops.

Husband works as employee [admin, etc]. Husband works from home office [no room at either shop for office].

Husband has a co car and a co van [pays BIK on car, no personal use on van so no BIK].

Husband uses van for travel to both work shops – still no BIK as it’s not classed as personal.

Wife has a car….claims business use on a % of total costs basis. [Home to work NOT claimed as business].

Q1 - Husband gives wife a lift to work in van….what now???

Q2 – Can husband use wife’s car for business mileage [starting from home], thereby increasing the business use %, or would he have to go to a shop to pick up the car, or disallow the first 4 miles [distance to largest shop] of any journey??