I have a home-based business. If during the 2014 tax year I drove a car:

* *C* miles for *car-maintenance errands*,
* *B* miles for *business errands*, and
* *P* miles for *personal errands*,

if the *total miles driven* is `C + B + P`, how do I calculate the *business miles driven* when deducting via the [actual expense method](http://www.irs.gov/taxtopics/tc510.html)? 

*Please include evidence for your answer that is specific to the problem of car-maintenance miles.*

**Please note: I am NOT deducting $.56/mile!** A couple people have assumed this already. The *actual expense method* means my deduction does not depend on the *total* miles I drove for business but on the *percent* of the miles I drove for business. But I still have to provide the totals.

**Examples of car-maintenance errands:**

* Driving a new car home from the dealership
* Driving to fill up at a gas station
* Driving to the mechanic
* Driving to the auto-parts store

**I think my options are:**

1. consider the maintenance driving as the same percent for business as the non-maintenance driving: `business = B + [C * B / (B + P)]`. 

	* This makes sense to me the most, because these miles are driven for *both* business and personal reasons (as the car is used for both), and the IRS's usual approach to mixed-use items is to multiply them by the percent business use.
2. (removed based on comments)
3. treat maintenance miles as business miles (because the car is necessary for business): `business = B + C`
4. treat maintenance miles as personal miles (because they are not solely for business): `business = B`
5. If I use the car mostly for business, count maintenance miles as business miles; otherwise, count maintenance miles as personal miles: `business = B + C if [B/(B+P)]>0.5 else business = B`

My common sense tells me to use #1 or #5, but taxes are not always common sense. I am looking for actual evidence from a reliable source for or against any of these options.