Business Mileage or Non-business Commute Mileage?

[Jon S.]

I'm using an app on my smart phone, called MileIQ, so I know where I have been. I have to classify whether the trips back and forth are business or not. So my question is, when leaving my home, which is also my home office, and driving to one of my properties, is that trip mileage business mileage? Or is that not business mileage because it's considered the same as a commute to work? I have one property that I am renovating, and it requires that I drive there several times per day to check on the renovation. In between, I usually drive home, and do work on the computer, etc. If those miles between home and job site are not considered business mileage I am going to lose a lot of business mileage deductions. I hope it's all business. Why else would I drive to the job site? If it is not considered business mileage, then what can I do to classify it as business mileage? Do I need to stop somewhere on the way, such as a gas station to pick up the daily newspaper, first? Or am I better off not tracking the trips and just taking a percentage of my overall annual mileage and classifying that as business use? Or is there another way? 

Also, if I go from job site to home depot, I know that is business mileage, but if I then drive from home depot to home, is that business mileage, or is that a commute?

If I stop at home while en route between home depot and the job site, is that all still business mileage? 

If I go back and forth from job site to home, directly, a few times a day, are they all considered business mileage, or commutes, or some are business and some are commutes? 

Very confusing, thanks in advance if you can clarify these scenarios.