Self employed

Your situation demands 2 separate Schedule Cs be filed - one for your real estate business and one for your driving/delivery business.   It is very important to keep detailed records for your mileage and those miles need to be separated between your 2 Schedule C returns.   You will have mileage for Instacart, Real Estate, and personal mileage.  Any miles spent looking for income (or showing a house) is deductible.  Just make sure you don't deduct any mileage twice and never include any trips that include personal activities.   In your scenario above, all miles driven while getting to the busy areas and waiting for work are deductible, but the leg of the trip dropping off or picking your child up from daycare would not be included.   Personal miles, just like commuting miles, are never deductible.   Mileage from showing a house would be deductible as well, but only on the real estate Schedule C. 

If possible, you can go back and create a log for the 2 months and deduct the business related miles for that period.   Using an app to track your mileage or keeping your own log is very important.  The IRS can disallow undocumented expenses so you cannot do too much record keeping….

Dead Miles Are Deductible if You are Seeking Income  -  Mileage discussion.

When Are Transportation Expenses Deductible?        Infographic (see page 12)

As far as your cell phone/tablet and data plan expenses, those can be allocated to each business based on the amount of activity you use them for.  You can use any reasonable means to allocate the expense between your businesses.   Example - if you use the phone for business 80% of the time, you can deduct 80% of the cost or bill each month.  Since you have multiple businesses, make sure you are not duplicating any expense and just like with the mileage, do not deduct any portion of any expense that is considered personal use. 

What can I expense or depreciate with the business safe harbor election?