Not sure how much information is needed, but let’s say something comes up that requires substantial driving which the employee is willing to do with their personal car.
Beyond their wage what do you think is a reasonable approach to compensating them for the use of their car? Specifically due to depreciation, wear and tear.
If it makes a difference I’m interested in the theoretical approach rather than what I can get away with or something like that.
There is no “reasonable”…there is a law regarding what you need to pay them. Note that skipping mileage reimbursement can lead to labor lawyers frothing at the mouth to come at you. So it’s best to just pay the standard.
Reference for a better understanding: https://www.paylocity.com/resources/resource-library/blog-post/employee-mileage-reimbursement/
I honestly avoid letting an employee use a personal vehicle on the clock because if something happens to them, or a bystander, on the clock you are liable for everything.