He asked what it is worth to me. Not what the real math is. Most people value their time, especially their time spent not working. Also I could definitely use that time with my hourly rate if the time spent walking prevented me from working overtime (and use 1.5 hourly rate).
Anyway I figure it costs me $18.67/day of real money. Loan payment (until next month) plus insurance, plus gasoline, plus maintenance guesstimate.